Add validation to the link form

[filipsobol]

Suggested merge commit message (convention)

MINOR BREAKING CHANGE (link): Add validation to the URL field to disallow empty URL by default. Closes #12501.

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Additional information

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[Witoso]

Update guide mention needed in this (how to restore previous behavior).

[mmotyczynska]

Approved ✅
Just a few typos to fix.

I like that you added InputUrlView class 👍

We must not forget about #15633 (comment). Do we have a follow-up issue or have we mentioned it somewhere?

[Witoso]

Let's reject/rethink IMHO. I want to mention that it is possible to add (relative) text into the link field right now (which will result in a relative link). As far as I can see, this behavior changed, as it's not being treated as a valid URL by the URL input field.

PR:

Current docs:

[Witoso]

The URL input itself looks great, I even wondered if it could be decided dynamically which one is used (when defaultProtocol config is provided use URL field). But then protocol can be anything, and it may require a more advanced logic (pattern validation).

[gorzelinski]

I only spotted some minor mistakes.

[mmotyczynska]

Some more typos to be fixed.

Generally looks good 👍 but I've found one case where the button is active even though the input text is empty. But this doesn't add an empty link to the editor because the link text is empty. IMO it's worth fixing so that the UI is consistent.

Screen.Recording.2024-01-08.at.11.41.27.mov

[filipsobol]

Generally looks good 👍 but I've found one case where the button is active even though the input text is empty. But this doesn't add an empty link to the editor because the link text is empty. IMO it's worth fixing so that the UI is consistent.

Fixed

[gorzelinski]

Now, it looks good to me!