diff --git a/test/css/index.js b/test/css/index.js
index e4f31f00a3..4e1cf23b5c 100644
--- a/test/css/index.js
+++ b/test/css/index.js
@@ -47,7 +47,7 @@ describe("css", () => {
 				css: read(`test/css/samples/${dir}/expected.css`)
 			};
 
-			assert.equal(dom.css.trim(), expected.css.trim());
+			assert.equal(dom.css.replace(/svelte-\d+/g, 'svelte-xyz').trim(), expected.css.trim());
 
 			// verify that the right elements have scoping selectors
 			if (expected.html !== null) {
@@ -62,7 +62,7 @@ describe("css", () => {
 
 					// dom
 					assert.equal(
-						normalizeHtml(window, html),
+						normalizeHtml(window, html).replace(/svelte-\d+/g, 'svelte-xyz'),
 						normalizeHtml(window, expected.html)
 					);
 
@@ -70,7 +70,7 @@ describe("css", () => {
 					const component = eval(`(function () { ${ssr.code}; return SvelteComponent; }())`);
 
 					assert.equal(
-						normalizeHtml(window, component.render(config.data)),
+						normalizeHtml(window, component.render(config.data)).replace(/svelte-\d+/g, 'svelte-xyz'),
 						normalizeHtml(window, expected.html)
 					);
 				});
diff --git a/test/css/samples/basic/expected.css b/test/css/samples/basic/expected.css
index 0d52d6d95f..1ece91b2e6 100644
--- a/test/css/samples/basic/expected.css
+++ b/test/css/samples/basic/expected.css
@@ -1,4 +1,4 @@
 
-	div[svelte-2278551596], [svelte-2278551596] div {
+	div[svelte-xyz], [svelte-xyz] div {
 		color: red;
 	}
diff --git a/test/css/samples/cascade-false-global-keyframes/expected.css b/test/css/samples/cascade-false-global-keyframes/expected.css
index 042db53426..a0741615b0 100644
--- a/test/css/samples/cascade-false-global-keyframes/expected.css
+++ b/test/css/samples/cascade-false-global-keyframes/expected.css
@@ -4,10 +4,10 @@
 		100% { color: blue; }
 	}
 
-	.animated[svelte-90785995] {
+	.animated[svelte-xyz] {
 		animation: why 2s;
 	}
 
-	.also-animated[svelte-90785995] {
+	.also-animated[svelte-xyz] {
 		animation: not-defined-here 2s;
 	}
diff --git a/test/css/samples/cascade-false-global/input.html b/test/css/samples/cascade-false-global/input.html
index 947edb6ab5..0350c826f5 100644
--- a/test/css/samples/cascade-false-global/input.html
+++ b/test/css/samples/cascade-false-global/input.html
@@ -6,7 +6,7 @@
 		color: red;
 	}
 
-	:global(div.foo) {
+	:global(div).foo {
 		color: blue;
 	}
 
diff --git a/test/css/samples/cascade-false-keyframes/expected.css b/test/css/samples/cascade-false-keyframes/expected.css
index 5377c86da7..583014ae41 100644
--- a/test/css/samples/cascade-false-keyframes/expected.css
+++ b/test/css/samples/cascade-false-keyframes/expected.css
@@ -1,13 +1,13 @@
 
-	@keyframes svelte-1647166666-why {
+	@keyframes svelte-xyz-why {
 		0% { color: red; }
 		100% { color: blue; }
 	}
 
-	.animated[svelte-1647166666] {
-		animation: svelte-1647166666-why 2s;
+	.animated[svelte-xyz] {
+		animation: svelte-xyz-why 2s;
 	}
 
-	.also-animated[svelte-1647166666] {
+	.also-animated[svelte-xyz] {
 		animation: not-defined-here 2s;
 	}
diff --git a/test/css/samples/cascade-false-pseudo-element/expected.css b/test/css/samples/cascade-false-pseudo-element/expected.css
index 3488839c46..5ee54847cb 100644
--- a/test/css/samples/cascade-false-pseudo-element/expected.css
+++ b/test/css/samples/cascade-false-pseudo-element/expected.css
@@ -1,12 +1,12 @@
 
-	span[svelte-2146001331]::after {
+	span[svelte-xyz]::after {
 		content: 'i am a pseudo-element';
 	}
 
-	span[svelte-2146001331]:first-child {
+	span[svelte-xyz]:first-child {
 		color: red;
 	}
 
-	span[svelte-2146001331]:last-child::after {
+	span[svelte-xyz]:last-child::after {
 		color: blue;
 	}
diff --git a/test/css/samples/cascade-false-universal-selector/expected.css b/test/css/samples/cascade-false-universal-selector/expected.css
index bb9155feb0..ca0a6de742 100644
--- a/test/css/samples/cascade-false-universal-selector/expected.css
+++ b/test/css/samples/cascade-false-universal-selector/expected.css
@@ -1,4 +1,4 @@
 
-	[svelte-2950902288] {
+	[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/cascade-false-universal-selector/expected.html b/test/css/samples/cascade-false-universal-selector/expected.html
index 732e063d51..e274b3e509 100644
--- a/test/css/samples/cascade-false-universal-selector/expected.html
+++ b/test/css/samples/cascade-false-universal-selector/expected.html
@@ -1 +1 @@
-<div svelte-2950902288=""></div>
\ No newline at end of file
+<div svelte-xyz=""></div>
\ No newline at end of file
diff --git a/test/css/samples/cascade-false/expected.css b/test/css/samples/cascade-false/expected.css
index 373c5aefed..39677a203a 100644
--- a/test/css/samples/cascade-false/expected.css
+++ b/test/css/samples/cascade-false/expected.css
@@ -1,12 +1,12 @@
 
-	div[svelte-781920915] {
+	div[svelte-xyz] {
 		color: red;
 	}
 
-	div.foo[svelte-781920915] {
+	div.foo[svelte-xyz] {
 		color: blue;
 	}
 
-	.foo[svelte-781920915] {
+	.foo[svelte-xyz] {
 		font-weight: bold;
 	}
diff --git a/test/css/samples/keyframes/expected.css b/test/css/samples/keyframes/expected.css
index c7d8540bdd..53d24fc691 100644
--- a/test/css/samples/keyframes/expected.css
+++ b/test/css/samples/keyframes/expected.css
@@ -1,9 +1,9 @@
 
-	@keyframes svelte-2931302006-why {
+	@keyframes svelte-xyz-why {
 		0% { color: red; }
 		100% { color: blue; }
 	}
 
-	[svelte-2931302006].animated, [svelte-2931302006] .animated {
-		animation: svelte-2931302006-why 2s;
+	[svelte-xyz].animated, [svelte-xyz] .animated {
+		animation: svelte-xyz-why 2s;
 	}
diff --git a/test/css/samples/media-query/expected.css b/test/css/samples/media-query/expected.css
index cecc50d860..5ea1a96059 100644
--- a/test/css/samples/media-query/expected.css
+++ b/test/css/samples/media-query/expected.css
@@ -1,6 +1,6 @@
 
 	@media (min-width: 400px) {
-		[svelte-411199634].large-screen, [svelte-411199634] .large-screen {
+		[svelte-xyz].large-screen, [svelte-xyz] .large-screen {
 			display: block;
 		}
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-contains/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector-contains/expected.css
index b48dfbe85a..957354dc6a 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-contains/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-contains/expected.css
@@ -1,4 +1,4 @@
 
-	[data-foo*='bar'][svelte-4224841812] {
+	[data-foo*='bar'][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-contains/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector-contains/expected.html
index 22a45b853e..c69d6b03c9 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-contains/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-contains/expected.html
@@ -1,2 +1,2 @@
-<div><p svelte-4224841812="" data-foo="foobarbaz">this is styled</p>
+<div><p svelte-xyz="" data-foo="foobarbaz">this is styled</p>
 	<p data-foo="fooBARbaz">this is unstyled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-equals-case-insensitive/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector-equals-case-insensitive/expected.css
index d20a6b98bf..218ef835be 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-equals-case-insensitive/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-equals-case-insensitive/expected.css
@@ -1,4 +1,4 @@
 
-	[data-foo='bar' i][svelte-4191913977] {
+	[data-foo='bar' i][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-equals-case-insensitive/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector-equals-case-insensitive/expected.html
index 1d65033d3e..4da16a0c2f 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-equals-case-insensitive/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-equals-case-insensitive/expected.html
@@ -1,2 +1,2 @@
-<div><p svelte-4191913977="" data-foo="BAR">this is styled</p>
+<div><p svelte-xyz="" data-foo="BAR">this is styled</p>
 	<p data-foo="BAZ">this is unstyled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-equals-dynamic/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector-equals-dynamic/expected.css
index 26fdc211a0..636d4206b9 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-equals-dynamic/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-equals-dynamic/expected.css
@@ -1,4 +1,4 @@
 
-	[data-foo='bar'][svelte-1339732946] {
+	[data-foo='bar'][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-equals-dynamic/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector-equals-dynamic/expected.html
index e27985b20d..f9cc8d8b5f 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-equals-dynamic/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-equals-dynamic/expected.html
@@ -1,2 +1,2 @@
-<div><p svelte-1339732946="" data-foo="whatever">this is styled</p>
+<div><p svelte-xyz="" data-foo="whatever">this is styled</p>
 	<p data-foo="baz">this is unstyled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-equals/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector-equals/expected.css
index 4a2cb3428e..636d4206b9 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-equals/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-equals/expected.css
@@ -1,4 +1,4 @@
 
-	[data-foo='bar'][svelte-2543760126] {
+	[data-foo='bar'][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-equals/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector-equals/expected.html
index 6dcb8cfaa3..4579673c46 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-equals/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-equals/expected.html
@@ -1,2 +1,2 @@
-<div><p svelte-2543760126="" data-foo="bar">this is styled</p>
+<div><p svelte-xyz="" data-foo="bar">this is styled</p>
 	<p data-foo="baz">this is unstyled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-pipe-equals/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector-pipe-equals/expected.css
index 8b57a24cd9..590f946bfb 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-pipe-equals/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-pipe-equals/expected.css
@@ -1,4 +1,4 @@
 
-	[data-foo|='bar'][svelte-1225676040] {
+	[data-foo|='bar'][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-pipe-equals/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector-pipe-equals/expected.html
index 1ba93cd6e5..37880da667 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-pipe-equals/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-pipe-equals/expected.html
@@ -1,3 +1,3 @@
-<div><p svelte-1225676040="" data-foo="bar">this is styled</p>
-	<p svelte-1225676040="" data-foo="bar-baz">this is styled</p>
+<div><p svelte-xyz="" data-foo="bar">this is styled</p>
+	<p svelte-xyz="" data-foo="bar-baz">this is styled</p>
 	<p data-foo="baz-bar">this is unstyled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-prefix/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector-prefix/expected.css
index 232c462c4b..8bcb510867 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-prefix/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-prefix/expected.css
@@ -1,4 +1,4 @@
 
-	[data-foo^='bar'][svelte-3106767242] {
+	[data-foo^='bar'][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-prefix/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector-prefix/expected.html
index 267528a516..a929494570 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-prefix/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-prefix/expected.html
@@ -1,2 +1,2 @@
-<div><p svelte-3106767242="" data-foo="barbaz">this is styled</p>
+<div><p svelte-xyz="" data-foo="barbaz">this is styled</p>
 	<p data-foo="bazbar">this is unstyled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-suffix/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector-suffix/expected.css
index 832f50cf3b..2d209085d0 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-suffix/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-suffix/expected.css
@@ -1,4 +1,4 @@
 
-	[data-foo$='bar'][svelte-207782622] {
+	[data-foo$='bar'][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-suffix/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector-suffix/expected.html
index 00bf78a6ca..71abcb7fa5 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-suffix/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-suffix/expected.html
@@ -1,2 +1,2 @@
 <div><p data-foo="barbaz">this is unstyled</p>
-	<p svelte-207782622="" data-foo="bazbar">this is styled</p></div>
\ No newline at end of file
+	<p svelte-xyz="" data-foo="bazbar">this is styled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-word-equals/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector-word-equals/expected.css
index 20cf2fd9e3..fcacb8704f 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-word-equals/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-word-equals/expected.css
@@ -1,4 +1,4 @@
 
-	[data-foo~='bar'][svelte-1786044856] {
+	[data-foo~='bar'][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector-word-equals/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector-word-equals/expected.html
index aef480d8ef..64244097a2 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector-word-equals/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector-word-equals/expected.html
@@ -1,2 +1,2 @@
-<div><p svelte-1786044856="" data-foo="qux bar">this is styled</p>
+<div><p svelte-xyz="" data-foo="qux bar">this is styled</p>
 	<p data-foo="qux baz">this is unstyled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector/expected.css b/test/css/samples/omit-scoping-attribute-attribute-selector/expected.css
index 662e453d83..283a92edca 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector/expected.css
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector/expected.css
@@ -1,4 +1,4 @@
 
-	[autoplay][svelte-240005720] {
+	[autoplay][svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-attribute-selector/expected.html b/test/css/samples/omit-scoping-attribute-attribute-selector/expected.html
index 254afb2a46..6a5b104388 100644
--- a/test/css/samples/omit-scoping-attribute-attribute-selector/expected.html
+++ b/test/css/samples/omit-scoping-attribute-attribute-selector/expected.html
@@ -1,2 +1,2 @@
-<div><video svelte-240005720 autoplay></video>
+<div><video svelte-xyz autoplay></video>
 	<video></video></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-class-dynamic/expected.css b/test/css/samples/omit-scoping-attribute-class-dynamic/expected.css
index 45b763d4de..ee6e96c597 100644
--- a/test/css/samples/omit-scoping-attribute-class-dynamic/expected.css
+++ b/test/css/samples/omit-scoping-attribute-class-dynamic/expected.css
@@ -1,4 +1,4 @@
 
-	.foo[svelte-2643270928] {
+	.foo[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-class-dynamic/expected.html b/test/css/samples/omit-scoping-attribute-class-dynamic/expected.html
index a51f22d968..c45e8d88a6 100644
--- a/test/css/samples/omit-scoping-attribute-class-dynamic/expected.html
+++ b/test/css/samples/omit-scoping-attribute-class-dynamic/expected.html
@@ -1,2 +1,2 @@
-<p svelte-2643270928="" class="whatever">this is styled</p>
+<p svelte-xyz="" class="whatever">this is styled</p>
 <p class="bar">this is unstyled</p>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-class-static/expected.css b/test/css/samples/omit-scoping-attribute-class-static/expected.css
index bf4e3cb73c..ee6e96c597 100644
--- a/test/css/samples/omit-scoping-attribute-class-static/expected.css
+++ b/test/css/samples/omit-scoping-attribute-class-static/expected.css
@@ -1,4 +1,4 @@
 
-	.foo[svelte-633959357] {
+	.foo[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-class-static/expected.html b/test/css/samples/omit-scoping-attribute-class-static/expected.html
index b972aa4cb1..24687444c4 100644
--- a/test/css/samples/omit-scoping-attribute-class-static/expected.html
+++ b/test/css/samples/omit-scoping-attribute-class-static/expected.html
@@ -1,2 +1,2 @@
-<p svelte-633959357="" class="foo">this is styled</p>
+<p svelte-xyz="" class="foo">this is styled</p>
 <p class="bar">this is unstyled</p>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-inner-class/expected.css b/test/css/samples/omit-scoping-attribute-descendant-global-inner-class/expected.css
index 5b0fe980e6..e8a40fc908 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-inner-class/expected.css
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-inner-class/expected.css
@@ -1,4 +1,4 @@
 
-	.foo[svelte-2122726581] .bar {
+	.foo[svelte-xyz] .bar {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-inner-class/expected.html b/test/css/samples/omit-scoping-attribute-descendant-global-inner-class/expected.html
index 008c017374..bbe7db5946 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-inner-class/expected.html
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-inner-class/expected.html
@@ -1 +1 @@
-<div svelte-2122726581="" class="foo"></div>
\ No newline at end of file
+<div svelte-xyz="" class="foo"></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-inner-multiple/expected.css b/test/css/samples/omit-scoping-attribute-descendant-global-inner-multiple/expected.css
index d09033651f..93ab1b04e5 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-inner-multiple/expected.css
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-inner-multiple/expected.css
@@ -1,4 +1,4 @@
 
-	div[svelte-3386191472] > p > em {
+	div[svelte-xyz] > p > em {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-inner-multiple/expected.html b/test/css/samples/omit-scoping-attribute-descendant-global-inner-multiple/expected.html
index db13732174..e274b3e509 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-inner-multiple/expected.html
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-inner-multiple/expected.html
@@ -1 +1 @@
-<div svelte-3386191472=""></div>
\ No newline at end of file
+<div svelte-xyz=""></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-inner/expected.css b/test/css/samples/omit-scoping-attribute-descendant-global-inner/expected.css
index 67a7fbed86..92d8f497d7 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-inner/expected.css
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-inner/expected.css
@@ -1,4 +1,4 @@
 
-	div[svelte-3744486606] > p {
+	div[svelte-xyz] > p {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-inner/expected.html b/test/css/samples/omit-scoping-attribute-descendant-global-inner/expected.html
index 4511b72221..e274b3e509 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-inner/expected.html
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-inner/expected.html
@@ -1 +1 @@
-<div svelte-3744486606=""></div>
\ No newline at end of file
+<div svelte-xyz=""></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-outer-multiple/expected.css b/test/css/samples/omit-scoping-attribute-descendant-global-outer-multiple/expected.css
index 9137c5bd8d..fa651566fb 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-outer-multiple/expected.css
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-outer-multiple/expected.css
@@ -1,4 +1,4 @@
 
-	div > section > p[svelte-3390623146] {
+	div > section > p[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-outer-multiple/expected.html b/test/css/samples/omit-scoping-attribute-descendant-global-outer-multiple/expected.html
index 35cfecee4f..c3b0783446 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-outer-multiple/expected.html
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-outer-multiple/expected.html
@@ -1 +1 @@
-<p svelte-3390623146="">this may or may not be styled</p>
\ No newline at end of file
+<p svelte-xyz="">this may or may not be styled</p>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-outer/expected.css b/test/css/samples/omit-scoping-attribute-descendant-global-outer/expected.css
index 46c00c646d..f62e230520 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-outer/expected.css
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-outer/expected.css
@@ -1,4 +1,4 @@
 
-	div > p[svelte-794545435] {
+	div > p[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-descendant-global-outer/expected.html b/test/css/samples/omit-scoping-attribute-descendant-global-outer/expected.html
index 5c3c80ea93..c3b0783446 100644
--- a/test/css/samples/omit-scoping-attribute-descendant-global-outer/expected.html
+++ b/test/css/samples/omit-scoping-attribute-descendant-global-outer/expected.html
@@ -1 +1 @@
-<p svelte-794545435="">this may or may not be styled</p>
\ No newline at end of file
+<p svelte-xyz="">this may or may not be styled</p>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-descendant/expected.css b/test/css/samples/omit-scoping-attribute-descendant/expected.css
index 548ef810ef..12d8add930 100644
--- a/test/css/samples/omit-scoping-attribute-descendant/expected.css
+++ b/test/css/samples/omit-scoping-attribute-descendant/expected.css
@@ -1,4 +1,4 @@
 
-	div[svelte-2557028325] > p[svelte-2557028325] {
+	div[svelte-xyz] > p[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-id/expected.css b/test/css/samples/omit-scoping-attribute-id/expected.css
index d62cda1725..09133ba7ff 100644
--- a/test/css/samples/omit-scoping-attribute-id/expected.css
+++ b/test/css/samples/omit-scoping-attribute-id/expected.css
@@ -1,4 +1,4 @@
 
-	#foo[svelte-2727164615] {
+	#foo[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-id/expected.html b/test/css/samples/omit-scoping-attribute-id/expected.html
index f9e629de56..cb6d2f2292 100644
--- a/test/css/samples/omit-scoping-attribute-id/expected.html
+++ b/test/css/samples/omit-scoping-attribute-id/expected.html
@@ -1,2 +1,2 @@
-<div svelte-2727164615="" id="foo"></div>
+<div svelte-xyz="" id="foo"></div>
 <div id="bar"></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-whitespace-multiple/expected.css b/test/css/samples/omit-scoping-attribute-whitespace-multiple/expected.css
index 590f547006..b9da332c6f 100644
--- a/test/css/samples/omit-scoping-attribute-whitespace-multiple/expected.css
+++ b/test/css/samples/omit-scoping-attribute-whitespace-multiple/expected.css
@@ -1,4 +1,4 @@
 
-	div[svelte-4032668709] section p[svelte-4032668709] {
+	div[svelte-xyz] section p[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-whitespace-multiple/expected.html b/test/css/samples/omit-scoping-attribute-whitespace-multiple/expected.html
index 7a3dea1431..874ad34012 100644
--- a/test/css/samples/omit-scoping-attribute-whitespace-multiple/expected.html
+++ b/test/css/samples/omit-scoping-attribute-whitespace-multiple/expected.html
@@ -1 +1 @@
-<div svelte-4032668709=""><section><p svelte-4032668709="">this is styled</p></section></div>
\ No newline at end of file
+<div svelte-xyz=""><section><p svelte-xyz="">this is styled</p></section></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute-whitespace/expected.css b/test/css/samples/omit-scoping-attribute-whitespace/expected.css
index fedf7985e1..cf24b2c3cc 100644
--- a/test/css/samples/omit-scoping-attribute-whitespace/expected.css
+++ b/test/css/samples/omit-scoping-attribute-whitespace/expected.css
@@ -1,4 +1,4 @@
 
-	div[svelte-4240344240] p[svelte-4240344240] {
+	div[svelte-xyz] p[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute-whitespace/expected.html b/test/css/samples/omit-scoping-attribute-whitespace/expected.html
index 06092e315c..874ad34012 100644
--- a/test/css/samples/omit-scoping-attribute-whitespace/expected.html
+++ b/test/css/samples/omit-scoping-attribute-whitespace/expected.html
@@ -1 +1 @@
-<div svelte-4240344240=""><section><p svelte-4240344240="">this is styled</p></section></div>
\ No newline at end of file
+<div svelte-xyz=""><section><p svelte-xyz="">this is styled</p></section></div>
\ No newline at end of file
diff --git a/test/css/samples/omit-scoping-attribute/expected.css b/test/css/samples/omit-scoping-attribute/expected.css
index f8adbd21a7..4bd7298c3d 100644
--- a/test/css/samples/omit-scoping-attribute/expected.css
+++ b/test/css/samples/omit-scoping-attribute/expected.css
@@ -1,4 +1,4 @@
 
-	p[svelte-1997768937] {
+	p[svelte-xyz] {
 		color: red;
 	}
diff --git a/test/css/samples/omit-scoping-attribute/expected.html b/test/css/samples/omit-scoping-attribute/expected.html
index 580168ced2..60c8d1ce9c 100644
--- a/test/css/samples/omit-scoping-attribute/expected.html
+++ b/test/css/samples/omit-scoping-attribute/expected.html
@@ -1 +1 @@
-<div><p svelte-1997768937="">this is styled</p></div>
\ No newline at end of file
+<div><p svelte-xyz="">this is styled</p></div>
\ No newline at end of file
diff --git a/test/css/samples/universal-selector/expected.css b/test/css/samples/universal-selector/expected.css
index 53f57d9083..ad9785f264 100644
--- a/test/css/samples/universal-selector/expected.css
+++ b/test/css/samples/universal-selector/expected.css
@@ -1,4 +1,4 @@
 
-	[svelte-2950902288], [svelte-2950902288] * {
+	[svelte-xyz], [svelte-xyz] * {
 		color: red;
 	}
diff --git a/test/validator/samples/css-invalid-global/errors.json b/test/validator/samples/css-invalid-global/errors.json
index 8aa138e3f2..71cb1f1261 100644
--- a/test/validator/samples/css-invalid-global/errors.json
+++ b/test/validator/samples/css-invalid-global/errors.json
@@ -1,8 +1,8 @@
 [{
-	"message": ":global(...) cannot be mixed with non-global selectors",
+	"message": ":global(...) must be the first element in a compound selector",
 	"loc": {
 		"line": 2,
-		"column": 1
+		"column": 5
 	},
-	"pos": 9
+	"pos": 13
 }]
\ No newline at end of file
diff --git a/test/validator/samples/css-invalid-global/input.html b/test/validator/samples/css-invalid-global/input.html
index 5d325a4cd1..518674424a 100644
--- a/test/validator/samples/css-invalid-global/input.html
+++ b/test/validator/samples/css-invalid-global/input.html
@@ -1,5 +1,5 @@
 <style>
-	:global(.foo).bar {
+	.foo:global(.bar) {
 		color: red;
 	}
 </style>
\ No newline at end of file