# Firefox 155.0.1

- Product: Firefox (https://whatsnew.fyi/product/firefox)
- Vendor: Mozilla
- Date: 2026-09-04
- Version: 155.0.1
- Original notes: https://www.mozilla.org/en-US/firefox/155.0.1/releasenotes/
- Permalink: https://whatsnew.fyi/product/firefox/releases/155.0.1

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.

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- **fixed** — Firefox becoming unresponsive on some pages that use CSS blur and backdrop filters together
- **fixed** — Sidebar not reappearing after restarting Firefox when the Hide tabs and sidebar option was turned on
- **fixed** — Some profile icons not being displayed in the account and application menus
- **fixed** — Current device being listed among connected devices in the account menu

###### Fixed
- Fixed Firefox becoming unresponsive on some pages that use CSS blur and backdrop filters together. (Bug 2068836)
- Fixed the sidebar not reappearing after restarting Firefox when the "Hide tabs and sidebar" option was turned on. (Bug 2065431)
- Fixed some profile icons not being displayed in the account and application menus. (Bug 2064729, Bug 2067734)
- Fixed the current device being listed among connected devices in the account menu. (Bug 2059763)
- Reference link to 155.0 release notes.
###### Unresolved
- Standard dynamic range (SDR) video in some formats can appear washed out on macOS. The issue is under investigation and a fix will ship in a future release. (Bug 2068961)