I too have this issue. What I've noticed is after it flips (selecting another tab and coming back does it), if you resize the browser window in any way (go from maximized to windowed or otherwise drag and resize it), it will revert back to normal until you click another tab again. Console seems to show UPDATE GL SIZE and final set zoom! after each instance of it flipping one way or the other. Example below: UPDATE GL SIZE! app.js:543 Final set zoom! app.js:563 window resize app.js:543 Final set zoom! app.js:542 UPDATE GL SIZE! app.js:543 Final set zoom! app.js:563 window resize app.js:543 Final set zoom! app.js:542 UPDATE GL SIZE! app.js:543 Final set zoom! app.js:563 window resize app.js:543 Final set zoom! app.js:542 UPDATE GL SIZE! app.js:543 Final set zoom! app.js:563 window resize app.js:543 Final set zoom! app.js:542 UPDATE GL SIZE! app.js:543 Final set zoom! app.js:563 window resize app.js:543 Final set zoom! app.js:542 UPDATE GL SIZE! app.js:543 Final set zoom! app.js:563 window resize app.js:543 Final set zoom! app.js:542 UPDATE GL SIZE! app.js:543 Final set zoom! app.js:563 window resize app.js:543 Final set zoom! app.js:542 UPDATE GL SIZE! app.js:543 Final set zoom! app.js:563 window resize app.js:543 Final set zoom! app.js:542 UPDATE GL SIZE! app.js:543 Final set zoom! Hope this helps! I did try clearing browser cache, logging all the way out of the site and back in, and disabling all extensions. None of that had any effect.