The rules a Windows study-focus app uses to decide that the window in front of you is a game, and what it does about it. Read from SeaSweep's source (15 November 2026).
Short answer: SeaSweep matches games two ways. Desktop games and launchers are matched by their process name (steam.exe, robloxplayerbeta.exe, valorant.exe…). Browser games are matched by a word in the tab title (poki, crazygames, roblox). A small allowlist of study sites always wins first. A match shows a lock screen, then closes the window (WM_CLOSE) or the tab (Ctrl+W).
What counts as "a game"?
When the student turns on the Games group, the app adds these rules:
| Matched by | Values |
|---|---|
| Process name | steam.exe, epicgameslauncher.exe, robloxplayerbeta.exe, minecraft.exe, minecraftlauncher.exe, riotclientservices.exe, leagueclient.exe, valorant.exe, battle.net.exe, fortniteclient-win64-shipping.exe |
| Tab-title word (only in a browser) | poki, crazygames, roblox |
Anything else can be added from a list of the programs that are open right now, by its .exe.
In what order are the rules checked?
Every 0.7 seconds, for the foreground window only:
- Protect the app itself. Task Manager, the Settings apps pages and "Uninstall a program" are matched first.
- Allow study sites. If the window is a browser and its title contains
wikipedia,khan academy,bitesize,duckduckgoorr/studying, nothing happens, even if another rule would match. - Docked rules. Process name first, then tab-title word if the process is a known browser (Chrome, Edge, Firefox, Brave, Opera, Vivaldi, Arc).
if (_browsers.contains(exe) && _studySites.any(title.contains)) return null; for (final r in _rules) { if (r.exe != null && exe == r.exe) return (r.label, 'docked', _CloseHow.window); if (r.site != null && _browsers.contains(exe) && title.contains(r.site!)) return (r.label, 'docked', _CloseHow.tab); } How is the game closed?
- A program:
PostMessage(hwnd, WM_CLOSE), the same message as clicking the window's X. - A browser tab: focus the window, then send Ctrl+W, so only that tab closes, not the whole browser.
- Debounce: after one lock, the guard waits 4 seconds before it locks again, so the lock screen does not stack.
What are the honest limits?
- Only the foreground window is checked. A game minimised in the background keeps running until you bring it forward.
- A tab-title match depends on the site's title. A game site whose title does not contain the word is not caught.
- No blocker is unbreakable. Force-closing the app is possible; the session is then logged as "lost contact" and earns nothing.
Common questions
How do I block video games on my PC while studying? Use a focus app that closes game launchers and game sites for a fixed time. SeaSweep's Games group covers Steam, Epic Games, Roblox, Minecraft, Riot, Valorant, Battle.net, Fortnite and the Poki and CrazyGames sites. It is free on the Microsoft Store.
Does it work on Mac? This is about the Windows app.
Get it: SeaSweep on the Microsoft Store (Store ID 9N3F281GJT5T).
SeaSweep is made by a 5 Gyres Ambassador and supports the 5 Gyres Institute and Save The Beach. @5gyres #5GyresAmbassador. For students: How to block video games on your PC while studying.
