Add read-only calendars to the sidebar

Currently, Microsoft 365 calendars to which you have Reviewer (read-only) access can not be added to Front's calendar sidebar. You can only add calendars for which you are an Editor.

Using the Find people search box, you can view the read-only calendar, but the + button to add it to your sidebar is missing. If you add the calendar in Outlook (web), it appears on both your Outlook and Teams sidebars, but not Front.

Front already supports adding teammates' calendars to your sidebar, which are read-only. I don't understand why you can't do the same for other calendars. This would be helpful for company calendars, where, for instance, HR is allowed to post events, but everyone else is only allowed to view.