Cannot change clock app to open when tapping Niagara at a glance widget's clock

Usually, to change the default clock app which opens when tapping the clock found in Niagara's at a glance widget, you'd go to system settings > Apps > the current clock app default > Open by default > Clear defaults (https://help.niagaralauncher.app/article/112-reset-default-app).
However, this option is currently not visible when only Niagara Launcher uses that app as the default.

This makes it impossible to switch default clock app, since no prompt is shown when tapping the clock widget.