Specifying a third party transaction URL crashes Bitcoin Qt #17467

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Expected behavior Core should save the provided URL and use it for transaction look ups

<!--- What behavior did you expect? -->

Actual behavior Core crashes and when started again the URL has not been saved.

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To reproduce Run Bitcoin qt with disablewallet=0. go to settings/options/display and specify a tx URL.

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System information

<!-- What version of Bitcoin Core are you using, where did you get it (website, self-compiled, etc)? --> Running v0.18.1 downloaded from bitcoincore.org

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Windows 10, AMD ryzen 2600, SSD

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relevant debug logs: GUI: Qt has caught an exception thrown from an event handler. Throwing exceptions from an event handler is not supported in Qt. You must not let any exception whatsoever propagate through Qt code. If that is not possible, in Qt 5 you must at least reimplement QCoreApplication::notify() and catch all exceptions there.

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I can't recreate this crash using master or 0.18.1, what URL are you using? I'm also not sure why disablewallet would make a difference here; is that the only time it happens?

I can't recreate this crash using master or 0.18.1, what URL are you using? I'm also not sure why disablewallet would make a difference here; is that the only time it happens?

You need to be using the wallet to access those settings, don`t you? First I tried removing an old url with an IP (aka leaving the field blank) and it crashed. Now I tried with http://bitchain.tk/ but literally any url crashes it.

You need to be using the wallet to access those settings, don`t you?

No, the third-party tx URL setting is always shown regardless of how Bitcoin Core is compiled / run. Can you run bitcoin-qt under lldb or gdb and get a backtrace?

I don't know what that means. I`ll look it up.

I can't reproduce it no matter how nonsensical the data I enter into that field.

Are you sure it's related to transaction URL or does any change to the configuration dialog cause a crash? It might be that some other field got corrupted (and it jut happens to trigger when you change the URL).

You might try running with -resetguisettings once to clear the GUI settings, and see if it keeps happening. If it solves the problem, I'd be interested in the backup guisettings.ini.bak that it writes to your data directory.

@laanwj It didn't work. I can still give you the guisettings.ini.bak if you want to.

Not necessary; it would only have been useful to know the settings that caused breakage, if a reset had fixed it.

@laanwj You were right. It's not the URL field alone. If I open the settings and then click OK (without even changing any of them) to apply them, Core crashes. Sometimes it says "Bitcoin Core can no longer continue safely and will now exit", sometimes it doesn't.

Is this still an issue with a recent version of Bitcoin Core? If yes, what are the steps to reproduce?