Currently about:tor is letterboxed when resized, despite being a built-in 'systemy' page (like about:preferences or about:config). We can remove the letterboxing for this page with this patch:
However, we may not want to do that and perhaps we want letterboxing for all content, regardless of whether it is a system page or not to avoid confusing users about different behavior.
I quite like it being LB'ed as it shows something is off with the rounding on new windows (all those quirks with toolbar showing, DPI not at 100%, etc) - i.e. before you load web content. Note that new tabs can grab the non-LB'ed size before it renders (see TZP or use this -> https://thorin-oakenpants.github.io/testing/newwinLB.html )
Pier Angelo Vendramechanged title from Consider adding about:tor to the list of pages that do not need letterboxing to Consider adding about:tor and others to the list of pages that do not need letterboxing
changed title from Consider adding about:tor to the list of pages that do not need letterboxing to Consider adding about:tor and others to the list of pages that do not need letterboxing
Ahahaha . Please notice that richard's patch above works, but I had some concerns about possible side effects.
There's a get needsLetterbox() { in browser/base/content/tabbrowser-tab.js, but the trivial way to modify it doesn't seem to work in my first test (I haven't cleaned the cache, though).