That bug has recently been reported: https://bugzilla.mozilla.org/show_bug.cgi?id=1794241

I believe it works much better in 'Horizontal' view. In 'Address Book' On the right side of the search is an icon - click on it and at the bottom of list select 'Switch to Horizontal Layout'

I was able to reproduce the same effect. To reproduce issue:

• View > Density > Compact
• Then I increased the font size: View > Font Size > Increase font

I had to increase a couple of times, but I saw same overlapping effect in Address Book.

To fix I did either of the following:

• Either: set - View > Density > Normal

This instantly fixed the overlapping font without needing to reduce the font size.

OR Keep using Density > 'Compact', but reduce the font size :

• View > Font Size > 'Reduce font size' or 'Reset font size'

Thanks very much for your kind help

I did as you said and went for HORIZONTAL

then I tried increasing font size,,, which it wouldn't allow me 

So then did ~ View~density~compact

So then,, just to experiment I went BACK to vertical layout,, and Lo and behold,,, it had fixed it,  and was now working and was readable !

You can  learn something everyday  !!

Sorry to take so long to to reply to your message suggestion,,  but I hadn't been that well for a week.

Advt wishes

John James

Good to hear you are now ok and the contact info is now easier to read.