@avl

Opera 50 crashed frequently, with no discernible pattern. In addition to that, the extension HTTPS Everywhere -- downloaded from Electronic Frontier Foundation -- which I had used in earlier versions of Opera, started going bad in Opera 50. Two or three times.
I just downloaded Opera 51. It has already crashed once. So we'll see. If it crashes again, I'll return to Opera 49 and try disabling auto-update.
If that doesn't work, I'll have to move on from Opera.
Thanks for the input.

So if Opera 50 is unstable and keeps crashing, and returning to an earlier version is at best a short-term solution, what's left. It seems I am then limited to Safari and searching for a new browser. Any suggestions?

@bobamamda-0

Is there nothing? If I simply drag Opera 50 to the trash and run the installer for Opera 49, what happens then?

Mac mini (Late 2014)
processor: 1.4 GHz Core i5
Memory: 4 GB 1600 MHz DOR 3
OS X 10.11.6
Opera 50.0.2762.67

I just upgraded from Opera 50 -- which kept crashing -- to Opera 51. And all my bookmarks are gone. Several YEARS worth of bookmarks are gone. This has never ever happened with any previous upgrade and I've been using Opera for more than four years. Is there ANYTHING I can do or am I totally screwed?

Mac mini (Late 2014)
processor: 1.4 GHz Core i5
Memory: 4 GB 1600 MHz DOR 3
OS X 10.11.6
Opera 50.0.2762.67

Opera 50 keeps crashing to the extent it has become unusable. I never had this problem with an earlier version of Opera. I still have the installers for Opera 43 & 49. I would like to re-install 49 (unless there is a reason 43 would be better?) but I'm not sure what to do. Do I simply drag 50 to the trash and run the installer for 49? I've never tried replacing a newer version of an application with an older version when there wasn't an uninstaller available.

@bobamamda-0

I am getting no response. Opera 50 keeps crashing or I get the spinning beachball of death and I can;t force quit.

I want to go back to Opera 49. Question: do I need to delete Opera 50 before I install?

I use Opera 50.0 on a mac mini running El Capitan (10.11.6)
This latest version crashes on a frequent basis. There is no discernible pattern. It even crashed when I first tried to load this web site. I reinstalled to see if that would help. It did not.
What can I do? Opera has been an excellent browser until now. But frequent crashes make it a browser not worth the trouble.