Why do my display configuration changes stay pending after I click Apply?

The changes remain pending until BetterDisplay successfully installs the system configuration. If Apply fails or authorization is cancelled, the red Apply/Undo notice can remain. That is different from successfully applying a configuration whose new modes still need activation or a restart.

Apply writes all pending display-model configuration changes, so review the staged edits before continuing. Follow any privileged-helper approval or administrator authorization requested by the app. If the operation reports an error, retain its full text rather than assuming the problem is the resolution you entered.

You can hold Shift while choosing Apply to request the administrator-prompt path. This still requires authorization. BetterDisplay also tries that path if its privileged helper fails. Choosing it is not a way to bypass system permissions.

If Apply still fails, open App Menu > Tools > Show Console, enable Logging, then reproduce the failure once and copy the relevant messages. Look for the error accompanying Something did not work out while applying the display configuration. A helper failure, cancelled authorization and script error are different outcomes. See console logging for how to capture the details.

An error naming another component needs investigation of that specific component. A generic script-error number alone does not justify removing unrelated plug-ins or resetting all permissions. A successful launch from Terminal also does not establish that verbose logging fixes the underlying problem.

After a successful Apply, complete any activation or restart offered by the app, then check the display's Display Mode menu. Selecting Undo instead discards the pending configuration edits. See system configuration changes and adding HiDPI resolutions for the full sequence.

For the underlying rendering method, see what flexible scaling and custom resolutions change.