# MobX 6.12.1

- Product: MobX (https://whatsnew.fyi/product/mobx)
- Vendor: MobX
- Date: 2024-03-22
- Version: 6.12.1
- Original notes: https://github.com/mobxjs/mobx/releases/tag/mobx%406.12.1
- Permalink: https://whatsnew.fyi/product/mobx/releases/6.12.1

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **fixed** — Prevent reaction from keeping a reference to the old value that would prevent garbage collection
- **changed** — Reduce memory overhead of tracking dependencies

###### Patch Changes

-   [`620f78c7`](https://github.com/mobxjs/mobx/commit/620f78c74e66bc532a96e28b26fd2d0ed1b67d54) [#3812](https://github.com/mobxjs/mobx/pull/3812) Thanks [@barroij](https://github.com/barroij)! - Prevent `reaction` from heeping a Reference to the OldValue that would prevent GC.


-   [`6111b093`](https://github.com/mobxjs/mobx/commit/6111b0939d0d3c0d46dc325ba6bbd5f740a161d3) [#3833](https://github.com/mobxjs/mobx/pull/3833) Thanks [@realyze](https://github.com/realyze)! - Reduce memory overhead of tracking dependencies