Here is my status report for August 2023.
At the beginning of the month, I continued with Tor Browser's Tor integration refactor.
The latest merge request  should be close to the final form I would like to have.
Apart from that, I worked on some Firefox code audits, such as pingsender2  and the API to save PDFs from pdf.js on Android .
I also investigated an issue about the favicon "supercookie"  and possible subpixel leaks from resolution media queries .
During the month, I also helped with rebases and releases.
At the end of the month, I started working on changes to allow system-wide installations of Mullvad Browser. I plan to continue from there these days and to fix the default browser functionality.
We are getting closer and closer to the release date for Tor Browser 13.0. So, please consider doing some alpha testing, especially if you do not use a "standard" setup (e.g., system tor daemon, etc.).
Thank you very much!
 Draft: Bug 40938 (part 4): Move from TorProvider=TorMonitorService+TorProtocolService to something that we could really call TorProvider (!721) · Merge requests · The Tor Project / Applications / Tor Browser · GitLab
 Review Mozilla 1746983: Re-enable pingsender2 (#41969) · Issues · The Tor Project / Applications / Tor Browser · GitLab
 Review Mozilla 1810761: Add API for saving a PDF (#41993) · Issues · The Tor Project / Applications / Tor Browser · GitLab
 Disable loading & keeping of favicon because it is trackable like persistent cookie (#42021) · Issues · The Tor Project / Applications / Tor Browser · GitLab
 add -moz-device-pixel-ratio to RFP (#42044) · Issues · The Tor Project / Applications / Tor Browser · GitLab
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