TYPO3 Core

This is a kind of follow-up of ticket #22113

It is currently possible (TYPO3 9.5.14 and 10.4.0-dev) to link to an explicit language version of a page with the following procedure:

Prerequisites¶

1) At least an additional language (e.g. with ID=1) and some translated pages
2) If you want to use the RTE, enable the "additional parameter selector" with the TSConfig

RTE.default.buttons.link.queryParametersSelector.enabled = 1

Procedure¶

1) Open the "link wizard" on the [header_link] field or using the RTE
2) On the "additional parameter selector" write "&L=1"
3) Select the appropriate target page

This works,but it has some usability flaws:

1) on the select link wizard you have to write &L=1 (for example) inside the "Additional link parameters" field so the editor must know what parameter is needed and its syntax
2) on the select link wizard, you must write &L=1 inside the "Additional link parameters" field before choosing the page, or the wizard popup will close and the procedure must be repeated.
3) If you click on some other page on the tree in the wizard window, the parameter field will become empty
4) the editor must know beforehand that the target page is translated

I set this issue as "feature", feel free to change it if needed.