Prevent margin from displacing content out of the viewport.

[Perritu]

Prevent code block from expanding the chat webview beyond it's horizontal limits by setting thread message div width to 100vw.

Solves #13056 #13055

Description

Added a css property to force the thread message block to match the viewport witdth.

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• The relevant tests, if any, have been updated or created

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[Perritu]

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[bluemoehre]

In my opinion vw isn't the best unit to use here. There's no guarantee that scrollbars won't take up space and this behavior may vary across OSes and window layouts / panel arrangements. CSS provides better alternatives like dvw and svw, which are designed to handle dynamic viewport changes more reliably.

Additionally, I believe this approach has another flaw: inline padding appears to accumulate (see the linked issues), which causes the inset area to be offset twice.

[Perritu]

In my opinion vw isn't the best unit to use here. There's no guarantee that scrollbars won't take up space and this behavior may vary across OSes and window layouts / panel arrangements. CSS provides better alternatives like dvw and svw, which are designed to handle dynamic viewport changes more reliably.

Additionally, I believe this approach has another flaw: inline padding appears to accumulate (see the linked issues), which causes the inset area to be offset twice.

Agreed.
I've modified the PR to align with TW conventions and to use the global chat object instead of the thread-specific one.