Thunderbird folder panels

Is there a way to increase the font size in the Thunderbird 60.8.0
(64-bit) folder panels? I have a 27 inch iMac running OS 10.13.6
and if I try to increase the font size in my inbox it only increases
the font size of the email, but the panel above it listing all the
emails is very small. I tried to look through all the extensions on
this site and didn’t seem to find one that would increase this text
size.

Please advise.

This should work for TB 60.8.0.

Theme Font & Size Changer

Thanks Walt