No idea what your mean. https://www.howtogeek.com/333110/how-to-customize-firefox-quantum-and-remove-the-white-space-around-the-title-bar/

like this

''_Al_ [[#answer-1039053|said]]'' <blockquote> like this </blockquote> Might be just the Theme you have chosen plus Language. My suggestion would be to try a bunch including the default ones info in above URL re Customize. Keep track if anymore make changes like that. If you have a bug, file a bug report. https://bugzilla.mozilla.org/ Bug Writing Guidelines : https://developer.mozilla.org/en-US/docs/Mozilla/QA/Bug_writing_guidelines That is about the only answer I have for you, try to fix in Customize as things can be dragged around and options plus 5 themes I guess. Why suggest use defaults in Customize is that if it can not be replicated in them then it probably is not a bug and is the Theme. I do not know for sure....... Have you tried here : https://bugzilla.mozilla.org/

Theme is https://addons.mozilla.org/ru/firefox/addon/space-fantasy/ I will try. Thanks!