What is your operating system?
Windows 7 64-bit / Windows 10 64-bit
What is your Shotcut version (see Help > About Shotcut)? Is it 32-bit?
Can you repeat the problem? If so, what are the steps?
Add a “Audio waveform visualization” filter to a complete track, happens whit a single audio in the track or several audio chunks with blank spaces between them.
Crash happens with or without other filters added to the track.
In this conditions Shotcut crashes when the playhead is set to the start, and therefore, as the project can be saved with the playhead at a random location, you can save it, but you will not be able to open it again because it will crash at oppening because the playhead is set at start.
Workarround to be able to reopen the project, open the .mlt file in and editor and delete manually the audioWaveform filter section.