[#6689] Setting admin permissions on CBSubs just 'spins'

The JS error is non-blocking so it's not what's causing the save to fail. Whatever is triggering the redirect is what is causing it to fail. Are you using latest CBSubs build where the permissions were moved to its own page or are you on an older release were permissions are a tab in CBSubs > Settings? If on older release please update as permissions should be on their own page within CBSubs > Settings after clicking Permissions on the toolbar.

If you're up to date and it's still doing this do you have a large amount of usergroups? It's possible you're hitting input limits if so.

I've created a replica of the site.
I've uninstalled ALL extensions other than CB and CB Plugins.
I've uninstalled all non-core extensions (plugins, modules, etc.)
I've cleaned the htaccess file (from all the 'security' settings added by Akeeba Admin)
I've even uninstalled CB Paid Subscriptions plugin and re-installed.

Still, having the same problems (changing access to CB Subs redirects to Control Panel and doesn't change the settings).

On a clean install with just CB/CBSubs the problem doesn't happen (spin still happens, but the change IS saved), just on this specific site.

I'm running out of things to test/track down.

Is there any possibility that a configuration within CB (or CBsubs) might be causing this? (Or a CB plugin)?

I think I MIGHT have narrowed down the issue.
The site has a lot of custom admin menus (using the new admin menu features in 3.7). After deleting all those custom menus our dev site seems to be working as expected.
Now to just narrow down and isolate which menu is causing the issue

It could be a routing problem with the backend menu items as CB doesn't take those into account. Try unpublishing any custom backend menu items to CB or any of CBs plugins to see if that solves it.

Thanks
That's what I did on the previous round; however, I did it after uninstalling everything else.
On a new replication of the site, just removing all the custom menus doesn't resolve the issue, so it must be multiple issues causing the problem.
I'm not going in 'reverse' order (having removed the custom menu items) to try to identify the 2nd conflict.

I do agree that this looks like a routing issue.

I would strongly encourage/request/plead that you make CBSubs permission settings work with the new custom admin menu items (as the core CBSubs permission settings already seem to do).

I'll post back here as soon as I track down any other issues and get this identified.

Well, completely deleting all the custom menu items (and menus) didn't resolve the problem.
Disabling all the non-core (other than CB) components/plugins/modules didn't resolve the issue.

The only things left (that I did previously but didn't do yet) are to completely uninstall those disabled exetensions (which I shouldn't think would be necessary) and to clean out the htaccess file again.

I'm guessing that the htaccess is the issue (because it can effect the routing); however, I'm growing concerned that CB's core permissions settings all work but CB Subs don't. Seems to me that there is a problem (or strangely different) way that the 2 different systems are working (or interacting with various routing issues).

If you know of an htaccess setting that is known to cause problems with cbsubs that would be helpful to know. Otherwise I'll try to debug that manually here.