Can’t search Outlook 365 (Exchange) from Windows Explorer search (or a script using search-ms:query) as I could with Outlook 2013

I had some simple AutoHotkey scripts to search Outlook, that took advantage of the fact that Windows Search/Indexing worked in Outlook, even hosted on an Exchange server. That worked in Outlook 2013. My organization recently upgraded to Outlook 365 (also on Exchange), and now the Windows Explorer search function (or search-ms:query called from a script) doesn’t find anything in Outlook.

Any ideas?
Thanks in advance!