1. MacOS: In the terminal, pass the --auto-open-devtools-for-tabs flag to while launching Edge.

/Applications/Microsoft\ Edge.app/Contents/MacOS/Microsoft\ Edge --auto-open-devtools-for-tabs https://web.dev

1. Windows: Right-click the Edge shortcut > Properties and add the flag at the end of the Target line. Alternatively, run the following from your command-line,

"C:\Program Files (x86)\Microsoft\Edge\Application\edge.exe" -auto-open-devtools-for-tabs