@teagow right, but you don't create it in Opera, right? An extension is basically a script that you write in the proper tools for that and, then, save/compile it so the extension can be used by the browsers.
So those new files should probably be in the same directory of the other files. At least it would be my first guess and what would make more sense.
@kilahchris The link to reset passphrase is in https://www.sync.opera.com/. If you are just seeing the Youtube video,it means that you have no synced data and don't need to use that link.
Now go to opera://settings/syncSetup and change or disable your passphrase.
found out that it was actually due to the wallpaper having a mod associated with it and that mod being active, so if this happens to you just go to your mods page and disable the respective mod.
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It depends on the game if you want to restart while you're playing. Some games allow you to restart where you left off, while others do not. In some games, there may be a "reset" or "prestige" option that allows you to start over. However, not every game has this. For further information, visit the game's website or support. If the game's developers don't already have this idea, you could suggest it if you can't reset.