Pls run Firefox in the safe mode and tell us if the problem still persist.

Hi there!

Sorry to hear you're experiencing problems with the new version.

Can you please try refreshing your installation by following the instructions on this page: https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings ?

Thank you for using Firefox.

This only happens with certain pages. Further information. (1) At first the affected pages load correctly. The problem starts at some random later time for no apparent reason. Restarting Firefox will cause the problem to go away for the time being. (2) When text is missing from a page, selecting ANY text size other than the default (i.e. ctrl/+ or ctrl/-) causes the missing text to reappear. However when the text size is restored to the default (ctrl/0) the text vanishes again. This is definitely a bug introduced in a recent update to Firefox. I suspect that it's an issue with the rendering engine for certain HTML constructs, which could explain why many pages always display correctly even when some others are missing text.

Is this happenning on 59.0.2?

I haven't seen it since updating, but it's early days yet. If it recurs I'll post back. So assume no news is good news.