# Thunderbird 153.1.1 — Thunderbird 153.1.1esr

- Product: Thunderbird (https://whatsnew.fyi/product/thunderbird)
- Vendor: MZLA Technologies
- Date: 2026-08-26
- Version: 153.1.1
- Original notes: https://www.thunderbird.net/en-US/thunderbird/153.1.1esr/releasenotes/
- Permalink: https://whatsnew.fyi/product/thunderbird/releases/153.1.1
- Labels: Platforms: Desktop

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 Thunderbird upgrade disabled composition toolbar Draft was not preserved when encrypted message send failed Account Hub prompted for calendar credentials after successful login Thunderbird crash…

- **fixed** — Thunderbird upgrade disabled composition toolbar
- **fixed** — Draft was not preserved when encrypted message send failed
- **fixed** — Account Hub prompted for calendar credentials after successful login
- **fixed** — Thunderbird crash