Button elements: text decoration isnot applying in the frontend on the button block

[MaggieCabrera]

Description

The text decoration settings for the button elements are not applying for the Button block on the frontend (they work on the editor).

Step-by-step reproduction instructions

Add this to theme.json inside styles:

"elements": {
	"button": {
		"typography": {
			"textDecoration": "underline"
		}
	},
}

Insert a button and check the editor and the frontend. Empty theme works fine for this.

Screenshots, screen recording, code snippet

Editor

Frontend

Environment info

No response

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

[carolinan]

When I add the typography setting above I see:
Comments form button -no underline on front
Search button -underline on front
Button block -no underline on front

[t-hamano]

The problem seems to be that .wp-block-button__link styles override the style by theme.json.
It may be effective to use :where to set the specificity to zero.