CSS layout issues as of late

Since a few days we're observing some odd flexbox behavior with our plugin (e.g. child flexbox divs not properly filling parents anymore). For reproducibility sake I was quickly checking this project out and it definitely doesn't look like it used to.

I reckon the office-ui-fabric-core/11.0.0 was updated underneath, but can't quite make the leap on what happened exactly in the last couple of days.

Current behavior

Just to give you an example from our plugin:

The body stretches the whole panel height, the ms-welcome doesn't want to properly fill the parent anymore:

Steps to Reproduce

Please provide detailed steps for reproducing the issue.

1. checkout this project
2. npm i
3. npm start

Context

Please provide any relevant information about your setup. This is important in case the issue is not reproducible except for under certain conditions.

• Operating System: win11
• Node version: 16.15.1 and 18.19.0
• Office version: Office Home/Business 2021, Microsoft® Excel® 2021 MSO (Version 2312 Build 16.0.17126.20132) 64-bit
• Edge Version 120.0.2210.133 (Official build) (64-bit)
• Tool version: cli is at 1.5.7

Failure Logs

nothing, just visuals