fix

packages/svelte/src/internal/client/dom/blocks/if.js

@@ -70,11 +70,11 @@ export function if_block(node, fn, elseif = false) {
 			active_fork.f ^= FORK_ROOT;
 
 			const fragment = document.createDocumentFragment();
-			const offscreen_condition = condition;
 			const offscreen_anchor = document.createComment('');
 
 			fragment.append(offscreen_anchor);
 
+			try {
 				const offscreen_effect = fn && branch(() => fn(offscreen_anchor));
 
 				active_fork.branches.push(() => {
@@ -106,6 +106,9 @@ export function if_block(node, fn, elseif = false) {
 						}
 					}
 				});
+			} finally {
+				active_fork.f |= FORK_ROOT;
+			}
 
 			return;
 		}

packages/svelte/src/internal/client/fork.js

@@ -145,6 +145,10 @@ export function fork(fn) {
 			flush_sync();
 
 			revert(active_fork);
+
+			if (f.pending === 0) {
+				f.callback();
+			}
 		});
 	} finally {
 		active_fork = null;