Zoom not working in Thunderbird

Owned by Marc Miller
Sept 14, 2021

Problem

You are trying to use the zoom function in Thunderbird, but it only changes the text size in the composition window.

Cause

This is probably due to permissions issues between Thunderbird and Google (what UCSB connect is based on)

Solution

Manually change the zoom factor in the Thunderbird backend settings:

Open the Menu and go to Preferences > General.

Scroll all the way down and at the very bottom

Click the Config Editor... button (accept the warning message).

You're looking for layout.css.devPixelsPerPx, you can just search 'pixels' and it will show up.

Click on layout.css.devPixelsPerPx and edit the default value of -1.0 (same as systme) to a scale factor you are comfortable with (example: 1.5, 2.0, 2.25, etc).

Clicking OK will allow you to immediately see your changes so you can dial it in pretty easily.

If you just use Thunderbird zoom with no backend changes it will only change the composition window text size, if you use the above, you can change both the message list and sidebar pane as well