Thanks for reporting this problem. I had a look at it myself and I was able to reproduce it by following very precise steps:
- Open the Preferences window.
- Without resizing the window, select the (previous to) last tab which requires the tabs list to be scrolled.
- Maximize the window.
- One arrow button stays enabled where they should both be disabled.
I made a quick workaround for this by adding a little extra if-block in the WndPrefTabs scroll function. Since this isn't a critical issue, I'm not going to push a new update just for this. If you find this really disturbing, feel free to replace your WndPrefTabs.js file with the attached fixed file.
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