Increase Font Size of Folder and Message List in Thunderbird

After getting an new 4k monitor you may wounder how to adjust the font setting of Thunderbird. May the font is a little bit to small. So you will go and search for the right setting. But there isn’t one in the UI. You need to use the configuration editor. (about:config). So open Options, scoll down to the end and open the „Config Editor“.
Now you can adjust this setting:

layout.css.devPixelsPerPx

Per default it is set to -1. Which means „use the system settings“.
But if you do not want to adjust the system settings for some reasons you can override it.
A value of 1.5 will scale the display by 150%. A value of 2.0 by 200%.
Find the setting you like 🙂