Docs: Update Electron info (#3320)

* Update Electron info

There were changes made that remove the env variable:
https://github.com/electron/electron/issues/48001

* Clarify Electron versions

docs/wiki/Application-Issues.md

@@ -2,14 +2,19 @@
 
 Electron-based applications can run directly on Wayland, but it's not the default.
 
-For Electron > 28, you can set an environment variable:
+For Electron ≥ 39, you can use the command-line flag if the app does not default to Wayland:
+```
+--ozone-platform=wayland
+```
+
+For Electron < 39, you can set an environment variable:
 ```kdl
 environment {
     ELECTRON_OZONE_PLATFORM_HINT "auto"
 }
 ```
 
-For previous versions, you need to pass command-line flags to the target application:
+For Electron ≤ 28, you need to pass command-line flags to the target application:
 ```
 --enable-features=UseOzonePlatform --ozone-platform-hint=auto
 ```