Twenty Fifteen and Twenty Sixteen: Table block "Fixed width table cells" toggle not working

[mrfoxtalbot]

Disabling the "Fixed width table cells" setting on the Table block has no effect when used in combination with Twenty Fifteen or Twenty Sixteen. It appears to be working ok in the editor preview but the public post displays fixed cells.

I tested Twenty Fourteen and Twenty Seventeen and it works fine.

[mrfoxtalbot]

Tables Block with "Fixed width table cells" setting disabled: Editor View

[mrfoxtalbot]

Tables Block with "Fixed width table cells" setting disabled: Twenty Sixteen

[mrfoxtalbot]

Table Block with "Fixed width table cells" setting disabled: Twenty Fifteen

[mrfoxtalbot]

This was reported originally in ​https://github.com/Automattic/wp-calypso/issues/93888

[sabernhardt]

It was reported earlier on #54120.