Programs are grouped with the program that launched them. How can I change that?

This morning, I launched Slack from the program list. Once it was up and running, I clicked a link therein, which launched Firefox. In fact, it launched four Firefox windows, each with many tabs, because Firefox remembers my previous session, and I’m disorganized like that. However, in the program switcher (Alt+Tab), the Firefox windows are…

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Ubuntu Studio 19.10 USB sound card not working anymore. Appears in /proc/asound/cards but no pcm device

I have a rather specific problem I couldn’t find anywhere else and maybe anyone has an idea what to do next. Coming back after the holiday season my usb sound card is being recognized, but no pcm playback or capture devices appear. I’m pretty sure I didn’t change or install anything apart from the regular…

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