"Because of the new extension system on Firefox, most of the functionality of the Theme Font & Size Changer is not available any more."

Fake extension, you can't change the font type or size, DO NOT INSTALL IT

Does not let me change font size.

It doesn't do what it says it does, it should be removed.

doesnt let you change font/font size anymore :(

Essential - was. Now no more. Sad...

This extension should be marked CLEARLY that it doesn't work anymore (or better - totaly removed). Don't waste your time attempting to install it - the only thing you will get is the information that it doesn't work in new FF versions.

使えない
（フォントはともかくサイズを変更したかったが色しか変更できなかった）

Can't change font size anymore on android

useless

Too bad this is still not working with latest FF 69. Add-on owner should update cup.aihedy.com to make it clear that it doesn't work anymore. One-star, which I'll happily remove once Dev updates to be more clear to avoid wasted time. If you want this working again, be sure to complete the survey at https://goo.gl/forms/Y6SGQfDxHPnMitMl2

Doesn't work with Firefox 68.0.2 :(