@ccm27 Goto the URL opera://about and take note of the "profile" path. Then, close Opera.
Then, open the "Preferences" file in the profile folder with JSONedit and switch to "Tree" mode like in the pic on the site. Or, use a different JSON editor if you're on Linux.
Expand the root/ui section. You should then see a "workspaces" section. Expand that.
What you want to do is compare the workspaces section with the workspaces section of the Preferences file for a standalone installation (or fresh profile using the --user-data-dir command-line switch if you're on Linux) to make sure things are correct (after creating the same workspaces in the standalone installation). If things are not the same, you need the fix the entries (while Opera is still closed) and save your changes.
Next, under root/ui/browser/sidebar/item_prefs, you want to make sure your see workspace entries 0 - 25 like in the Preferences file of the standalone installation. Under root/ui/browser/sidebar/item_prefs/visibility, you want to make sure there are workspace entries 0 - 25 there too like in the standalone installation.
The reason things might be messed up in your Opera profile is because workspace settings changed a bit along the way while they were being developed. If you've been upgrading for a while, you might have gotten some old workspace settings stuck in there.
Now, if you don't mind recreating your workspaces, adding the tabs back in them and re-customizing your sidebar, you can right-click on the "root/ui/browser/sidebar" node and choose "delete node". You can then do the same for the "root/ui/workspaces" node. Deleting them and saving your changes should cause Opera to recreate them fresh when starting up, which might solve your problem. Of course, if you use Opera Sync and sync your settings and open tabs etc., I'm not sure what will happen.
You can back up your "Preferences" file and "sessions" folder in the profile folder (or the whole profile folder) first if you want, just in case.
