Update: It switched itself back to Google after a windows update. I'm on the Windows 10 Insider Preview (Fast Ring). The machine did a full restart after the update. I'm going to test if restarting the machine causes the issue.

Opera version 38.0 and previous versions. I'll switch the search to Bing via the settings, and randomly it will switch it back to Google. I haven't specifically found a event in which this occurs or is triggered.

I've noticed that after updates to the browser, the default search engine changes back to Google. I'm a Bing guy and it's quite frustrating. Any way around this?