The Memory Purge
macOS is highly optimized to maximize battery life and system performance. When you have dozens of Safari tabs open, macOS aggressively manages the memory they consume. If you navigate away from a specific tab for an extended period, or if you switch to a memory-intensive application like Final Cut Pro, macOS might automatically purge the background Safari tabs from active RAM. When you finally click back to that older tab, Safari is forced to completely refresh and reload the webpage from the internet. This is disastrous if you were halfway through filling out a long web form, writing a comment, or paused a video, as all that unsaved data is instantly wiped out by the refresh.
Managing Safari’s Tab States
Apple does not provide a simple graphical toggle in Safari’s preferences to stop macOS from automatically refreshing background tabs, as it is tied deeply to the operating system’s core memory management. However, you can mitigate it using specific terminal commands or third-party extensions.
First, check your Safari settings. Open Safari, go to Safari > Settings (or Preferences) in the menu bar, and look under the Advanced tab. If you see an option for “Internet plug-ins,” ensure it is set to save power, but be aware this doesn’t stop the full page reload. To truly force Safari to keep tabs active, power users often rely on the Debug menu. Open the Terminal application and type: defaults write com.apple.Safari IncludeInternalDebugMenu 1 and press Enter. Restart Safari. You will now see a “Debug” menu at the very top. Inside this menu, you can look for experimental flags related to “Tab Suspension” or “Process Swapping” (these change depending on the macOS version) and disable them to force tabs to stay in memory.