4.50

Breaking: New extension SDK version (user extensions need to be updated)
New: Twitch.tv game library integration #496
New: Ability to add new library providers via plugins
New: Steam friends button added to Modern theme
New: Option to reopen Playnite's window when game stops running
New: More detailed progress info when downloading metadata
New: Greek localization (by @metallic77) #752
New: Italian localization (by @StarFang208) #446
Fix: Updated RetroArch profiles
Fix: Updated emulator profiles (by @By6r9)
Fix: General UI polish and fixes (by @spektor56, @hellosputnik, @kkjdroid, @t-miller) #716
Fix: Play time detection of Window Store apps not working properly if game is not installed on c: drive
Fix: Play time detection not working properly if game is running with elevated rights
Fix: Memory leak when switching between fullscreen and desktop modes
Fix: Incorrectly set database path when using portable version
Fix: Updated Nintendo/Nintendo Pro fullscreen buttons (by @ClearStrelok) #713
Fix: Playnite crashes when trying to sort by category #722
Fix: Play time not being counted when starting game via URL
Fix: InstallDir not working properly with relative paths #735
Fix: High CPU usage when game is running
Fix: Game icon not being set when importing via drag'n'drop
Fix: Fullscreen mode doesn't respect "When game starts" settings #737
Fix: Filter panel opening when using main search box #738
Fix: Crash when launching Windows Store game #725
Fix: Crash when importing emulated games #727
Fix: Detecting installed apps not working on Windows 7 properly