This is doable in a theme component, the method by @Alankrit_Choudh can work but I would recommend adding a custom ember initializer instead that overrides the URL in discourse instead of relying on window.onload here.
This is doable in a theme component, the method by @Alankrit_Choudh can work but I would recommend adding a custom ember initializer instead that overrides the URL in discourse instead of relying on window.onload here.