Browser client not updating mail

Browser client not updating mail

About 24 hours ago (so sometime on Feb 11) the email client I keep running in one tab of my browser stopped receiving mail updates. If I change folders and change back I see new mail. Same thing if I hard refresh the browser. But no updates without taking those those explicit actions. Also, no notifications.

My android phone which has the Zoho mail client still gets new mail notifications (which is how I've managed to NOT miss some very important emails, thankfully). 

I've made no configuration change that I can recall. I have tried in both Brave browser (my main browser) and Chrome with the same result. 

Any thoughts? Thank you.