As mentioned here (https://dev.office.com/blogs/make-your-add-ins-available-in-the-office-ribbon) all new taskpane submissions to the Office store must use commands to pass validation.
After experimentation with add-ins with and without commands, it appears that existing add-ins without commands will automatically reload when the file is re-opened in Excel online (e.g. via OneDrive, Dropbox). Add-ins with commands do not reload upon re-opening the file, and must be re-installed through the add-in store each time the file is opened.
I know there have been similar questions asked here:
- Online Excel Add In on workbook re-opening
- Automatically loading Word Task Pane Office Add-in
- Keep Office add-in task pane open at document load
And perhaps more specifically here:
- Office Web App - Show task pane on load where the suggestion is to remove add-in commands.
Given that I cannot submit an add-in without add-in commands any more, how can I have the add-in persist / show up in the ribbon on subsequent re-opening of the file (currently our add-in users have to constantly re-install the add-in) ?