Actually I have been able to narrow this down. It seems its an interaction between “envira gallery” and simple press. If I disable either one, customizer for my theme will work, but when both forum and envira gallery are running, I can’t.

This is going to be a challenge.

quite odd…   does the theme actually change and work?  or does it die in middle?

any more info in the error log?  

since I am unfamiliar with this other plugin, anything unique that it does?  does it use any js libraries?

I guess luckily, changing something in the customizer will be few and far between…

With both Envira and Simplepress running I can not get to customizer at all. If disable either one, I can get it to work. 

There might be other conflicts between the two also since I have some java issues with Envira Galary with file name picks when Simplepress is running.

 Enduser side of both of them seems to be working fine, the issues with the conflicts seem to be in the WP Admin console side of things.

file name picks???  not following…

did you have a chance to check the error log on forum – toolbox – error log? and then also your php error log after the error occurs…

do you have a link to this envira gallery plugin? is it free?

Envira Gallery is a very popular high end gallery plugin. It is extremely fast and completely responsive. It has been fast replacing larger systems that use the free ones like nexgen.

https://enviragallery.com/

I have had them look into some errors before and they also noticed clashes between their software and SimplePress (Their “defaults” addon, etc). But they haven’t addressed them as they evidenty have not had many people running the combo.

In reference to file name picks, when I have SP running, none of the boxes that allow me to pick a file or picture work in Envira Gallery. It is a java script error, but I just can’t find it.

Well, we obviously cannot look since it’s a premium plugin. 

Does the plugin use any js frameworks?  In particular in the wp admin. We typically load most js on our panels only on the admin. Guess the customizer could be loading more since it’s mimicking a page load. 

Not sure what you mean by file picks… 

On forum – integration – page and Permalink do you loaf js in footer or header? Might be worth switching and see if we get lucky. 

No luck in changing the loading order.

Let me see if I can put in a request to the Envira Developer to give you a copy for the purposes of checking for conflicts. I can’t possible believe I am the only one in the WP world using them on the same site.

Can I get an email address that gets to you guys internally that I can forward to the Envira Developers.

do you have a link to your site?  might see obvious conflicts if we can inspect the code…

you can get us a support at simple-press dot com…

first thing that sticks out is that there are multiple versions of plupload loaded…    one if from simple press and the other is likely coming from your gallery plugin but cant tell for sure…  

my guess is they are conflicting…  wp runs a heavily customized plupload script while we run the stock one…   think we were using ours before wp released theirs, but definitely a potential problem…  

also see that the calendarize plugin is loading bootstrap library incorrectly…  bootstrap is known to conflict with the wp jquery ui library… and as such, jquery ui must be loaded after bootstrap…  

I doubt the bootstrap library issue is causing your problem… it normally manifests itself differently so may not be related…  though this could certainly be the case for what you call file picks…  bootstrap loaded after jquery ui causes jquery ui buttons to not function properly…

Believe the main issue is double loading of the plupload library… we have not taken the considerable amount of time and effort it would take to redo our file uploader to use the version of plupload that wp now comes with (instead of loading the stock one)…  especially since we have only had a handful of conflicts since wp launched with plupload…  so may not have any good answers for you…

Can you tell me if you actually use the gallery plugin on the forum page?  If not, you could just not load it on the forum page to bypass the conflict…  this would be done with a loading plugin such as Plugin Optimizer…  lets you load specific plugins on specific (or general) pages…

Calenderize does have the option of not loading jquery if it is loaded somewhere else, and I think I can change its loading order. 

Envira Gallery is not used on any forum pages.

I will see if I can play around with loading orders again.

Philip Gordemer said
Calenderize does have the option of not loading jquery if it is loaded somewhere else, and I think I can change its loading order. 

If a plugin is coded to the proper WP standards and API an option is not required. Using the proper enqueue  commands ensures only a single copy is loaded.

Envira Gallery is not used on any forum pages.

I will see if I can play around with loading orders again.  

So the best bet would be not to load the gallery plugin ion the forum page. That would remove the conflict.

Did you check the Plugin Organizer plugin as I said for easily controlling order and if loaded on specific pages?

I will give the plugin organizer a try.

let us know… it can be helpful if plugins load lots of stuff on every page rather than just where used…