Customizer Not Working after WP 5.9 Update

Hi there,

i would begin by checking for plugin conflicts by temporarily disabling all plugins.
If thats not the issue then Right Click > Inspect the customizer and look for any Red Console Errors

David,
Just chiming in to say I'm having the same difficulty after WP5.9 upgrade:
– Customizer white-screens for every WP5.9 site I've checked (I run GeneratePress on lots of sites, it's AWEsome!),
– it doesn't seem plugin-related (I disabled every plugin on a staging build site, no change in Customizer misbehavior), and
– it DOES seem browser-specific – Chrome acts fine, Safari white-screens

In all cases stepping back to 5.8.3 resolves the problem, but I'd like to move up to 5.9 as soon as I'm comfortable my Safari-using clients won't be discommoded by the misbehavior. Hope this helps you diagnose and correct the issue!

https://gtarebuild.xyz and https://gfxstaging.xyz are two staging builds that exhibit the problem, for your reference; I could issue you temporary admin credentials on either or both if that'd help in any way. Thanks in advance for your timely and expert assistance!

:Benjamin

Hey guys,

Any chance you can activate a Twenty series WP default theme and test if the issue occurs there as well?

a-HA. The noted misbehavior DOES assert itself in Safari, even switched to Twenty Twenty-Two (and GP Blocks switched off, just for good measure.) Looks like it's nothing to do with GeneratePress, just a fight between 5.9 and Safari. Sorry for the trouble ... but you might want to make a general announcement of some sort to the GP user community? Might save you a bunch of time on frontline customer support "It's not our fault" emails until the bug's squashed.

Thanks for the quick resolution,
:Benjamin

We will handle the support questions as they come in.

Thanks for clarifying!