I have set up 4 workspaces, each with a number of tabs. When restarting my PC these tabs are restored sometimes, but other times they are completely empty.

I think this may be possibly related to extensions, some of which are from the Chrome store. I currently use Roboform, Athenticator,
Evernote Web Clipper, Save to Pocket and Install Chrome Extensions.

I prefer to use Opera as my default browser, but this gives me too much work to restore tabs. Also, there are no tabs listed in my history, which would have made it easier to restore them all.