Also note that Opera can be set to start when Windows starts. The setting is at the URL opera://settings/onStartup.

Another thing you might do is open the Windows Task Scheduler, create a new task that runs:

"C:\Users\yourusername\AppData\Local\Programs\Opera\opera.exe" --autostart

as your user every minute.

With the --autostart part, Opera shouldn't open a new window if Opera is already running. In other words, Opera will automatically open back up eventually after you close it. Of course, it might be in your face then. No guarantees this will work and no guarantees that it doesn't cause issues during while Opera is updating.

There's also:

opera.exe --no-startup-window

that loads the base Opera processes without showing a window until you load opera.exe normally. This might make things faster for Opera to start up, but didn't do any testing to prove that. When you exit Opera though, all Opera processes still exit, so you'd have to run the command again after you close Opera if you want Opera to stay loaded in memory.

If you want to test it, after you close Opera, hit Windows key + r to open up the run dialog, type cmd and press enter. Then, type:

"%localappdata%\Programs\Opera\opera.exe" --no-startup-window

and press enter.

Then, confirm Opera is running in the Windows task manager.

Then, do a bunch of things on your computer for a while and then try to launch Opera with its shortcut to see if there's any improvement. Windows has a prefetch cache though that makes a program you just used load up faster, so it might not help too much.

On a different note, if you do set Opera to run at startup in its settings, you could launch regedit, goto "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run" and edit the "Opera Stable" string to add a space and then --no-startup-window to the end. Then, when Windows starts, Opera will start, but not show any windows. Then, when you want to actually launch Opera, it might launch faster. In other words, it'd be like preloading Opera's processes. You'll have to test if your open tabs are retained properly all the time though, so back up your open tabs if they're important. Also, keep this race condition in mind. Also note that once you close Opera, you'll have to run opera.exe --no-startup-window again. You can create a shortcut for that.

So, if you're in to advanced stuff, you can play around with the above (as an alternative, not a solution). If not, you can ignore all of this.