Chrome on Linux - query the browser to see what tabs are open?

Indeed there is a command line option which can open the door to a running chrome (chromium) process --remote-shell-port. Through this "debugging back-door" you may be able the get the list of open tabs.

• Look at chromedevtools for further inspiration.

UPDATE:

Chrome DevTools is deprecated and not supported anymore since Version >17.0.950.* See WebKit-Protocol manual if the new Debug-Framework provides similar manners to accomplish the task.

Here is a more general solution (works with other applications as well) by querying the X window under focus using xdotool

while true; do 
  xdotool getwindowfocus getwindowname; 
  sleep 10; 
done

This outputs the following for instance:

Tilix: Defaultpeter-ThinkPad-T5801: peter@peter-ThinkPad-T580: ~
Chrome on Linux - query the browser to see what tabs are open? - Stack Overflow - Google Chrome
Local KVM
untitled — Atom
untitled — Atom
Open File
iostat_xtmz_3.out — ~/Work/KappAhl/Test1 — Atom
Tilix: Defaultpeter-ThinkPad-T5801: peter@peter-ThinkPad-T580: ~*

Chrome on Linux - query the browser to see what tabs are open?

For chromium :

strings ~/'.config/chromium/Default/Current Session' | 'grep' -E '^https?://'