How to adjust the font size?

Hi seraphir Adjustment of font size within the app is not currently available however you can increase the size via Androids system wide font settings. Developers have stated in the below github comment. https://github.com/thunderbird/thunderbird-android/issues/9709#issuecomment-3249281014 <Blockquote>We’ve removed these settings as part of the ongoing UI redesign, since the previous way of changing font sizes no longer works with the new design system. We’re working on alternative options to bring back some customization in a future update.</blockquote> You can show your interest in the feature by raising it on [https://connect.mozilla.org/t5/ideas/idb-p/ideas/label-name/thunderbird%20android Mozilla connect]. It's then open to community votes.