I’m sure you have many explanations, but here’s a related tip: Get an addon that suspends tabs after X minutes. You get to set X. If you leave a browser open and many tabs (Raises hand) you want that quick mark if you want to go back, but you don’t need to have it in memory. When X happens, it kills that, but keeps the tab. When you click on the tab next time, it simply refreshes and brings it back alive again. It’s a go to addon for all my systems.
For Firefox I use Tab Suspender, here are the options available:
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