If a Remote Desktop session keeps ending after a quiet stretch, the first question is where the timer lives. There are two places, and only one of them is yours.
On your own PC
Your local machine can sleep, lock or run a screensaver, any of which can interrupt a session you started from it. Power settings are the right tool for those.
On the server
Windows Server and many corporate setups apply session limits through Group Policy: an idle limit, a disconnected-session limit and an active-session limit. When one of these fires, the server ends or disconnects the session regardless of what your PC is doing.
Where a browser extension fits
If your remote session runs in a browser tab, such as a web-based remote desktop or admin console, the page itself may log you out after a period without activity. An extension that simulates page activity can help with that page-level timer. It does nothing for a server-side policy, or for sessions that run outside the browser.
How to tell which one you're hitting
- If your own screen locked or went to sleep first, it's local.
- If you get a message about the session ending because of an idle limit, it's the server.
- If it always happens at exactly the same interval, suspect a policy.
For server-side limits, the right move is to ask whoever administers the machine. Those limits exist for capacity and security reasons, and working around them can cause problems for you and for others.