This is one of the reasons I'd prefer to move everyone over to the browser version wherever possible. NW.js has been a regular source of odd and awkward bugs that aren't in Chrome, and the fewer people use NW.js, the less that will be a problem. I think a lot of people started using the NW.js desktop app in the first place for the local file system access, which can be done in Chrome now, so you don't need NW.js for that and can move over. However I do appreciate that specifically for testing NW.js features in your games, it's still useful to use the NW.js desktop app. (There's also the NW.js remote preview that lets you test NW.js while using the editor in the browser which might be another option to try out.)
Follow the link to nightly releases to find the very latest builds: https://dl.nwjs.io/live-build/
Like any software's nightly builds they can be hit-and-miss on quality, but the 0.48 version indicates that this particular rendering issue does seem to be already fixed. So it's just a matter of time to wait for the next update to roll out, or you can try just using the nightly release already.