Privacy Browser Android

When opening browser and expanding Navigation drawer, Back, Forward, Scroll to Bottom and History buttons, all of them are highlighted (clickable), though you can't press any of them (supposing the user clears history).

Also, navigating by loading bookmarked websites causes the same issue on this buttons, except Back and History, obviously.

Curiously, loading a website, for example https://providers.xmpp.net, and searching for the word "missing" (what will automatically scroll down to that word) previously caused the same issue: i.e. Scroll to Top was not highlighted though it was clickable. That's how I found the issue, but after updating WebView from 122.0.6261.90 to 125.0.6422.165 and rebooting the device, that particular issue disappeared.

As far as I could experiment, scrolling to the bottom of the Navigation drawer and then back to the top makes buttons appear as they should. This workaround is successful in all the scenarios I could test:
1. loading from bookmarks
2. loading by typing URLs,
3. opening the app

On scenario 1 and 2 you can scroll down and up through the website and buttons are still displayed incorrectly. You can even click on links witouth any change. Sometimes long-pressing a link on a website makes buttons display correctly.

So it's seems quite confusing to me. I don't know if this is an issue of Privacy Browser because updating WebView makes things display a bit differently. But I also restarted my device in between so I don't know if that could have something to do.

Device: Motorola E2 surnia
Android: 10 (API 29)
WebView: currently 125.0.6422.165 (com.android.webview)