That's a new one for me, and I haven't seen that on any of the systems I've tested the code on. Though I'm not surprised that the UI can randomly break, especially considering I'm not really a UI programmer.
`sandboxed-tor-browser` follows the XDG Base Directory Specification, and writes a JSON format config file to a standard location (`$XDG_CONFIG_DIR/sandboxed-tor-browser/sandboxed-tor-browser.json`), so it should be easy to check what's actually set.
nb: While human readable, any/all bugs relating to "I edited it and it broke" will be ignored.
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