> For the complete documentation index, see [llms.txt](https://developer.thunderbird.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.thunderbird.net/add-ons/updating/updates-for-thunderbird-140.md).

# Updates for Thunderbird 140+

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A list of individual changes in Thunderbird's own code is no longer published here.
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Modern WebExtensions are generally stable and do not require ongoing updates to remain compatible. For Experiment add-ons, the number of potential changes in Thunderbird's core code has grown so large that tracking and documenting every incompatibility is not an effective use of resources.

It has proven more effective to discuss compatibility issues during the [**weekly add-on developer call** or on the **add-on developer mailing list**](/add-ons/community.md). These forums allow developers to raise questions, share experiences, and collaborate on solutions with the community.

Changes to the WebExtension APIs continue to be documented alongside our [API documentation](https://webextension-api.thunderbird.net/en/mv3/).