UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36

Steps to reproduce the problem:
1. In a tab, open some web page, e.g. google.com
2. Open the Dev Tools
3. In Dev Tools, turn on mobile emulation by clicking on the Mobile icon on the top-left corner of the Dev Toolsç
4. Close this tab
5. In a new tab, open some web page, e.g. google.com
6. Open the Dev Tools

What is the expected behavior?
Should not switch to mobile emulation. There's no good reason to. Nobody has requested it. I have only asked you to open the Dev Tools. The fact that the last time I used dev tools in some other random tab I switched to mobile emulation is no indication that I want to turn on mobile emulation now just because I open dev tools. Also, it is completely useless anyway, because in order to see a sensible emulation, I will need to reload anyway (and you obviously don't want to reload automatically when I open DevTools, do you). So, there's no reason to expect mobile emulation to be remembered and turned on automatically when opening dev tools.

What went wrong?
it does.

Did this work before? No 

Chrome version: 70.0.3538.77  Channel: n/a
OS Version: 
Flash Version: