I run roughly six applications regularly:

- One browser window (with tabs)

- One terminal window (with tabs)

- Signal (not a web app, for good reason, though frankly I'd be thrilled if it lived in a browser tab anyway as an app being served to localhost)

- The occasional PDF viewer for PDFs I'm working on (anything loaded from the web gets viewed in the in-browser PDF viewer, but when I'm creating presentations or papers or similar, I have a terminal and a PDF viewer both half-maximized)

- Video player for local videos (mpv)

- Music player for local music (quodlibet)