A: Yes. In windowed mode, your desktop compositor (DWM.exe) also renders. In exclusive fullscreen, the game gets direct access to the display buffer, typically boosting FPS by 10-20%.
Do not use third-party "borderless gaming" applications that hook into the game’s .exe file. If you are playing the browser version, stick to browser settings. If you are playing the downloaded PC client, use the in-game video settings only. External overlay tools can trigger false positives. The Verdict: Browser vs. Downloaded Client for Fullscreen The 1v1.LOL community is split between browser players and those who downloaded the native PC client from the Microsoft Store or official website.
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