Unclear error message when trying to edit a custom template without permission

[tsteur]

• Given you have a user that has write and publish permission tag manager but not for custom templates.
• Try to edit a custom tag
• Click Save
• See error message that shows up:

The error message in red isn't helpful in that situation. Yes there is a yellow warning from the beginning when opening the tag, but this may be missed easily.

The request that fails does have the actual error message that is a bit more readable:

Expected behavior: The error message from the request should be shown in red.
Alternatively: Don't allow editing of any of the fields and neither allow submitting the form.

[snake14]

Thank you for creating this issue @tsteur . I like the idea of making sure that the form can only be edited/submitted when permissions allow.