"valid_elements" syntax for element removal when empty attributes needs example

[blindspeed90]

Documentation/Product Version
6.8.5

Links to Page(s) affected
https://www.tiny.cloud/docs/tinymce/latest/content-filtering/#valid_elements

Description of Issue

This entry:

"! - Enables removal of elements with no attributes such as . They can still have content though."

needs example, as I had to look into the code to find the "elementRuleRegExp" in tinymce.js and break it apart to figure out its' usage. Here, it needs to be something like "-span![!style]", the "!" in front of "[", whereas "!style" means a required attribute.

Suggested Fix
Adding the example with that comment would help.

Also, breaking this table up or adding a column to show what control characters can go where. Better than that, from that RegExp, having a template documented like BNF is far clearer (brief and incomplete, but you get the point):

=[","]
=["/"][]["[""]"]
= "+" | "-" | "#"
= "@" | "*" |
=
=
="" | "!"

[blindspeed90]

The editor removed all my BNF tags I had as an example above.