Disallow subscript and superscript at the same time

[jacekbogdanski]

Type of report

Feature request

Provide description of the new feature

Currently, enabling subscript and superscript on the same content will result in producing the below HTML:

<p><sup><sub>foobar</sub></sup></p>

Many popular text editors (like MS Word) don't allow to style text with subscript and superscript at the same time. It's not recommended to change the current implementation, but we could introduce an opt-in configuration option that would give more freedom in choosing proper behavior:

1. Select text and apply subscript:
   <p><sub>foobar</sub></p>
2. Select the same text and apply superscript:
   <p><sup>foobar</sup></p>

[jswiderski]

Please note that we have closed such an issue in te past - #3303

[jacekbogdanski]

The reasoning in #3303 (comment) is not totally valid. It's true that both elements can be nested in each other, but that doesn't mean we can't improve a user experience by giving a more predictable interface to manipulate rich content.

[NavnathKumbhar]

You closed #3303 mentioning about Phrasing content. The rule just says:

Most elements that are categorized as phrasing content can only contain elements that are themselves categorized as phrasing content, not any flow content.

From my understanding, It is just about what it can contain as its child.
The standard do no say that we can not provide such an improvement in the question.

[CKEditorBot]

Closed in #5312