chore: remove deprecated app.enableMixedSandbox() (#17894)

docs/api/breaking-changes.md

@@ -81,6 +81,15 @@ powerMonitor.querySystemIdleTime(callback)
 const idleTime = getSystemIdleTime()
 ```
 
+## `app.enableMixedSandbox`
+
+```js
+// Deprecated
+app.enableMixedSandbox()
+```
+
+Mixed-sandbox mode is now enabled by default.
+
 ## Preload scripts outside of app path are not allowed
 
 For security reasons, preload scripts can only be loaded from a subpath of the [app path](app.md#appgetapppath).

docs/api/chrome-command-line-switches.md

@@ -181,6 +181,11 @@ logging level for all code in the source files under a `foo/bar` directory.
 
 This switch only works when `--enable-logging` is also passed.
 
+## --no-sandbox
+
+Disables Chromium sandbox, which is now enabled by default.
+Should only be used for testing.
+
 [app]: app.md
 [append-switch]: app.md#appcommandlineappendswitchswitch-value
 [ready]: app.md#event-ready