Unable to inspect Android device via Chrome://inspect

This is a known issue.

The answer in the link (changing USB mode from MTP to PTP) did work for me for some time, however others have had less success, and my setup has now regressed to the erratic connection you are seeing.

Personally, I just try to play quick draw and click on the device when it's listed before it disconnects again, which after a bit of practice doesn't take too long, and once you've done that, the actual inspect tools don't have the same erratic connect/disconnect problem so you should be fine until you physically disconnect the device.

This should be resolved in a future version of Chrome.

I know this is an old question, but nonetheless, this is what helped me:

• while in Chrome chrome://inspect/#devices page is opened
• turn off USB Debugging,
• turn on USB Debugging again

The phone will ask me if I trust the connection...