Somebody referred to it as GUI font rendering changed in latest update of Thunderbird, I don't know if this is correct, but for for sure it now looks different. Enlarges the display of the message list, and the folder tree view.
Can I change it to look the way it did before this update? If not, can I use System Restore to an earlier point to get round this, and disable automatic Thunderbird updates?
Finally a solution that works, mine is currently set at 1.45, this works best for me.
Looking around in the Web, it turned out that there are lots of complaints about the tiny fonts.
I found a solution, it is not exactly perfect but certainly gets around the tiny font size problem:
https://support.mozilla.org/en-US/questions/1297871
It means using “About Config” by clicking on “Config Editor” at the very bottom of the page in: Thunderbird/Preferences/General, then accepting the “risk” (I understand there is no such risk, just a sort of in joke), then searching for “pixel” in the search field there, and clicking twice on this line: layout.css.devPixelsPerPx .
In the window that opens change the default “-1” to something bigger, but not too big, then click OK. In my case “3” works. Make sure that the “-” has been removed when changing the value from -1 to some multiple 0f 0.5, while keeping in mind that larger than 3, going by my own experience, might be too large and inconvenient, as changing from -1 on up increases all the font sizes everywhere in Thunderbird (and only in “Thunderbird”), including the “Inbox”, so everything there gets crowded and some goes out of sight if one chooses a number that is too big. The moment you click OK, you’ll see the effect of the change in the very “Config Editor” page you are in.
