# Svelte changelog
## 3.19.2
* In `dev` mode, display a runtime warning when a component is passed an unexpected slot ([#1020](https://github.com/sveltejs/svelte/issues/1020), [#1447](https://github.com/sveltejs/svelte/issues/1447))
* In `vars` array, correctly indicate whether `module` variables are `mutated` or `reassigned` ([#3215](https://github.com/sveltejs/svelte/issues/3215))
* Fix spread props not updating in certain situations ([#3521](https://github.com/sveltejs/svelte/issues/3521), [#4480](https://github.com/sveltejs/svelte/issues/4480))
* Use the fallback content for slots if they are passed only whitespace ([#4092](https://github.com/sveltejs/svelte/issues/4092))
* Fix bitmask overflow for `{#if}` blocks ([#4263](https://github.com/sveltejs/svelte/issues/4263))
* In `dev` mode, check for unknown props even if the component has no writable props ([#4323](https://github.com/sveltejs/svelte/issues/4323))
* Exclude global variables from `$capture_state` ([#4463](https://github.com/sveltejs/svelte/issues/4463))
* Fix bitmask overflow for slots ([#4481](https://github.com/sveltejs/svelte/issues/4481))
## 3.19.1
* Do not treat modifications to `$$props` as updates to a store called `$props` ([#4368](https://github.com/sveltejs/svelte/issues/4368))
* Deconflict `value` parameter name used in contextual bindings ([#4445](https://github.com/sveltejs/svelte/issues/4445))
* Fix dev mode validation of `{#each}` blocks using strings ([#4450](https://github.com/sveltejs/svelte/issues/4450))
## 3.19.0
* Fix indirect bindings involving elements with spreads ([#3680](https://github.com/sveltejs/svelte/issues/3680))
* `$capture_state`/`$inject_state` now act on the component's entire state, rather than its props ([#3822](https://github.com/sveltejs/svelte/pull/3822))
* Warn when using `` and `Foo` is dynamic ([#4331](https://github.com/sveltejs/svelte/issues/4331))
* Display compilation warnings in `svelte/register` in dev mode ([#4364](https://github.com/sveltejs/svelte/issues/4364))
* Fix unneeded updating of keyed each blocks ([#4373](https://github.com/sveltejs/svelte/issues/4373))
* Throw runtime error in dev mode for non-array-like values in `{#each}` blocks ([#4408](https://github.com/sveltejs/svelte/issues/4408))
## 3.18.2
* Fix binding to module-level variables ([#4086](https://github.com/sveltejs/svelte/issues/4086))
* Improve parsing error messages when there is a pending unclosed tag ([#4131](https://github.com/sveltejs/svelte/issues/4131))
* Disallow attribute/prop names from matching two-way-bound names or `{shorthand}` attribute/prop names ([#4325](https://github.com/sveltejs/svelte/issues/4325))
* Improve performance of `flush()` by not using `.shift()` ([#4356](https://github.com/sveltejs/svelte/pull/4356))
* Permit reserved keywords as destructuring keys in `{#each}` ([#4372](https://github.com/sveltejs/svelte/issues/4372))
* Disallow reserved keywords in `{expressions}` ([#4372](https://github.com/sveltejs/svelte/issues/4372))
* Fix code generation error with precedence of arrow functions ([#4384](https://github.com/sveltejs/svelte/issues/4384))
* Fix event handlers that are dynamic via reactive declarations or stores ([#4388](https://github.com/sveltejs/svelte/issues/4388))
* Fix invalidation in expressions like `++foo.bar` ([#4393](https://github.com/sveltejs/svelte/issues/4393))
## 3.18.1
* Fix code generation error with adjacent inline and block comments ([#4312](https://github.com/sveltejs/svelte/issues/4312))
* Fix detection of unused CSS selectors that begin with a `:global()` but contain a scoped portion ([#4314](https://github.com/sveltejs/svelte/issues/4314))
## 3.18.0
* Fix infinite loop when instantiating another component during `onMount` ([#3218](https://github.com/sveltejs/svelte/issues/3218))
* Make autosubscribing to a nullish store a no-op ([#2181](https://github.com/sveltejs/svelte/issues/2181))
## 3.17.3
* Fix updating a `` inside an `{#if}` or other block ([#4292](https://github.com/sveltejs/svelte/issues/4292))
* Fix using RxJS observables in `derived` stores ([#4298](https://github.com/sveltejs/svelte/issues/4298))
* Add dev mode check to disallow duplicate keys in a keyed `{#each}` ([#4301](https://github.com/sveltejs/svelte/issues/4301))
* Fix hydration of `` when starting from SSR-generated code with `hydratable: true` ([#4310](https://github.com/sveltejs/svelte/issues/4310))
## 3.17.2
* Fix removing attributes during hydration ([#1733](https://github.com/sveltejs/svelte/issues/1733))
* Disallow two-way binding to a variable declared by an `{#await}` block ([#4012](https://github.com/sveltejs/svelte/issues/4012))
* Allow access to `let:` variables in sibling attributes on slot root ([#4173](https://github.com/sveltejs/svelte/issues/4173))
* Fix `~=` and class selector matching against values separated by any whitespace characters ([#4242](https://github.com/sveltejs/svelte/issues/4242))
* Fix code generation for `await`ed expressions that need parentheses ([#4267](https://github.com/sveltejs/svelte/issues/4267))
* Preserve JavaScript comments from the original component source where possible ([#4268](https://github.com/sveltejs/svelte/issues/4268))
* Add some more known globals ([#4276](https://github.com/sveltejs/svelte/pull/4276))
* Correctly apply event modifiers to `` events ([#4278](https://github.com/sveltejs/svelte/issues/4278))
## 3.17.1
* Only attach SSR mode markers to a component's `` elements when compiling with `hydratable: true` ([#4258](https://github.com/sveltejs/svelte/issues/4258))
## 3.17.0
* Remove old `` elements during hydration so they aren't duplicated ([#1607](https://github.com/sveltejs/svelte/issues/1607))
* Prevent text input cursor jumping in Safari with one-way binding ([#3449](https://github.com/sveltejs/svelte/issues/3449))
* Expose compiler version in dev events ([#4047](https://github.com/sveltejs/svelte/issues/4047))
* Don't run actions before their element is in the document ([#4166](https://github.com/sveltejs/svelte/issues/4166))
* Fix reactive assignments with destructuring and stores where the destructured value should be undefined ([#4170](https://github.com/sveltejs/svelte/issues/4170))
* Fix hydrating `{:else}` in `{#each}` ([#4202](https://github.com/sveltejs/svelte/issues/4202))
* Do not automatically declare variables in reactive declarations when assigning to a member expression ([#4212](https://github.com/sveltejs/svelte/issues/4212))
* Fix stringifying of attributes in SSR mode when there are spread attributes ([#4240](https://github.com/sveltejs/svelte/issues/4240))
* Only render one `` in SSR mode when multiple components provide one ([#4250](https://github.com/sveltejs/svelte/pull/4250))
## 3.16.7
* Also apply actions in the order they're given along with other directives ([#2446](https://github.com/sveltejs/svelte/issues/2446), [#4156](https://github.com/sveltejs/svelte/pull/4156))
* Check whether a dynamic event handler is a function before calling it ([#4090](https://github.com/sveltejs/svelte/issues/4090))
* Correctly mark event handlers as dynamic when they involve an expression used in a `bind:` elsewhere ([#4155](https://github.com/sveltejs/svelte/pull/4155))
## 3.16.6
* Fix CSS specificity bug when encapsulating styles ([#1277](https://github.com/sveltejs/svelte/issues/1277))
* Apply directives in the order they're given ([#2446](https://github.com/sveltejs/svelte/issues/2446))
* Fix destructuring in `let:` directives ([#2751](https://github.com/sveltejs/svelte/issues/2751))
* Preserve whitespace around ``s in `