# MobX 6.1.6

- Product: MobX (https://whatsnew.fyi/product/mobx)
- Vendor: MobX
- Date: 2021-02-11
- Version: 6.1.6
- Original notes: https://github.com/mobxjs/mobx/releases/tag/mobx%406.1.6
- Permalink: https://whatsnew.fyi/product/mobx/releases/6.1.6

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** — Reduced overall memory usage of MobX in production builds by skipping the generation of debug identifiers
- **removed** — Removed the internal mapid_ field of Reaction

###### Patch Changes

-   [`9b195b17`](https://github.com/mobxjs/mobx/commit/9b195b17bd661b9c0c4ab3a8ef323e23c2f118e4) [#2780](https://github.com/mobxjs/mobx/pull/2780) Thanks [@iChenLei](https://github.com/iChenLei)! - The overall memory usage of MobX has been reduced in production builds by skipping the generation of debug identifiers. The internal `mapid_` field of Reaction has been removed as part of the change.