I used to use a really awful old fire stick, it was supremely laggy.
Every now and then I had to go through and manually force stop the applications I wasn’t using, this would always drastically improve performance.
Is this a thing with Roku?
No. When you exit an app or press Home on your remote the app is effectively killed. When a screensaver runs, the current app may continue running in the background, although its execution is mostly suspended. Other than that, Roku devices can't run two apps at the same time. There's some system stuff (like checking for and maybe installing updates and downloading ads) that will happen while it's on the Home Screen and analyzing network traffic there's plenty of Netflix stuff that happens (Netflix has always been "special" and doesn't play by the same rules as other apps), but that's about it. That doesn't mean that a "System restart" once in a while isn't helpful like rebooting any computer and should be the first thing tried when having any kind of issue.
This definitely happens!! My kid go the remote now the TV won't work. Trued restarting and everything, deleted apps, took wifi off nothing. Now in the background a kid show keeps playing and it won't let me do anything else
I think yes it does on some apps. I have Spectrum streaming and sometimes when I click on the app the next day and it opens up to the home screen it's showing shows and times from the day before. It never updates to the current day and time. It also takes forever to change channels and such. I have to go into my Roku TV and do a system restart or "restart app" in order to get it to reset to current day and time. The system restart is the only way to get it to go back to not taking forever to change channels. It totally acts like it has been running in the background the whole time the TV was off cause I've got the habit of just turning the TV off and not exiting to the home screen first before turning the TV off. It's also not the only app I've seen show signs of supposedly running in the background.
There's an Instant Resume feature that apps can take advantage of, but the app is suspended and isn't running in the background. That may be what's happening.