Buttons' appearance in disabled fieldset

[datvm]

What is affected?

Component

Description

When a button or icon button is in a disabled fieldset, it correctly does not trigger click event. However, the appearance is not changed to match:

Reproduction

Lit Playground

Workaround

We have to manually keep track of the buttons' state and disable/enable each of them.

Is this a regression?

No or unsure. This never worked, or I haven't tried before.

Affected versions

1.4.0

Browser/OS/Node environment

Browser: Google Chrome Version 123.0.6312.86 (Official Build) (64-bit)

OS: Windows 11

[asyncLiz]

This is probably due to button not implementing formDisabledCallback()

[datvm]

Interesting, I believe this is related to #5049. I thought it was completed because the click behavior is working correctly with fieldset. Right now the styling is depending on [disabled]. I think it should be changed to :disabled instead.

I have created 2 PRs. If both PRs are approved it should fix this and #5049 as well.