Crash when switching from/to bitstream analysis window

[Christian]

Describe the bug
Sometimes, YUView crashes when switching back/forth from the analysis window.

To Reproduce

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots
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Version (please complete the following information):

• OS: [e.g. iOS]
• Version [e.g. 2.2.1, commit gb283bgrj]
• If you compiled YUView yourself then which Qt version did you use?