Since update cannot edit/change roles or capabilities

Try to deactivate plugin and activate it back.
Is it the latest version 4.18.1?

Yes it’s 4.18.1

Tried deactivating and reactivating and same error.

I’m using the Membership plugin if that makes a difference but never had a problem editing roles before this update.

I suppose that Membership plugin is not the case.

Version 4.18 introduced own capabilities for URE:
https://www.role-editor.com/user-role-editor-4-18-new-permissions/
Those capabilities should be added to the ‘administrator’ role automatically.
Does your user have ‘administrator’ role or something other?

I am the only administrator.

I had a backup with 4.14 so I reverted to that and am able to edit roles without issue.

Could you please check if ‘ure_%’ custom capabilities were added to the administrator role?

When I update to 4.18.1 no ure_% capabilities are added at all.

These are the only custom capabilities (from Membership plugin) that are listed in my profile:

membershipadmin, membershipadmindashboard, membershipadminmembers, membershipadminlevels, membershipadminsubscriptions, membershipadmincoupons, membershipadminpurchases, membershipadmincommunications, membershipadmingroups, membershipadminpings, membershipadmingateways, membershipadminoptions, membershipadminupdatepermissions

Thank you. Confirm please, that your administrator user has exactly built-in “administrator” role, not any renamed copy of it.

If plugin fails to add capabilities during version update, it should re-add them apparently during manual activation. Is it possible at this site to re-activate version 4.18.1 with WP_DEBUG constant at wp-config.php set to true? Any additional information will be helpful.

No capabilities were added after manual activation.

I am just using standard WP Administrator role – I have not edited these or created new roles except for the roles that are added by Membership.

The only debug errors that could possibly be related are these:

Notice: Undefined index: name in /home/neagus1/crushtraders.com/wp-includes/capabilities.php on line 127

Notice: Undefined index: name in /home/neagus1/crushtraders.com/wp-includes/capabilities.php on line 127

These are from WP core.

Yes, it could be related to the issue.
Could you please send here or to support [at-sign] role-editor.com the result of this SQL query:

SELECT * FROM wp_options WHERE option_name='wp_user_roles';

It is your site user roles data. I will test plugin with them then.

Recommendation: it is not secure to show a real path to your site installation, ‘wp-includes/capabilities.php’ part is enough.