To download Thunderbird 91.13.0:
: Patched a vulnerability where the address bar could be spoofed via XSLT error handling. download thunderbird 91.13.0
| Risk | Description | |------|-------------| | | Version 91.13.0 contains known vulnerabilities that are fixed in versions ≥102. Do not use with live email accounts on untrusted networks. | | Broken Add-ons | Many modern extensions require Thunderbird ≥115. | | Profile Incompatibility | Opening a profile with a newer Thunderbird version will upgrade it, making it unusable with 91.13.0. Always back up your profile first. | | macOS Notarization | Version 91.13.0 may fail to run on macOS Ventura (13) or later due to expired signing certificates. | To download Thunderbird 91
Disable update checks:
Before diving into the download process, it’s essential to understand why this specific version remains in demand years after its release. | | Broken Add-ons | Many modern extensions
Downgrading your profile from Thunderbird 115+ to 91.13.0 is not supported and will likely break your address book, calendar, and message database schema. Instead, export your data: