- Edited
So if both of these were implemented:
URL Modal window (what Peek could be called in Orion) - any links clicked on a pinned tab will open in a modal-style overlay. It creates a temporary new session in that modal that goes away if I close the peek window (Xing it) or hit another key like ESC. I can move the current URL in Peek to a full browser window if I want to continue working on that "branch".
Temporary browser window (Little Arc in Orion): any links clicked from external apps open in a browser window with only basic chrome (maybe back/forward/refresh and access to extensions - no address bar). Any external links (or links in the temporary browser window) I click on will take over whatever's in the temporary browser window. I can merge the temporary browser's URL into my current window/tabs if I want it to stick around. This closes the temporary browser window and opens a new tab/browser window, depending on current settings).