@Pavel Spichonak, handle all status codes >= 400. You don't need individual handlers for 401, 402, 40X, etc, but all 4xx and 5xx response-codes should result in a user notification. A good display option is ErrorModal. The native browser alert is really a fallback, effectively indicating "this is an unhandled exception", but if that's all we have time for, it's fine by me; it's better than swallowing the error because at least it tells the user something went wrong.

@Cheryl Malmborg @Zak Burke could you please list what status codes we need to handle and what error messages we need to show for this status codes? And should we use native browser dialog(alert) or our custom dialog?

@Stephanie Buck I would leave this as a P2. I don't know how common it is for the errors to be ignored, but ignoring them can lead to problems that take a long time to surface and troubleshoot.

@julie.bickle, by default resources are configured with throwErrors: true which means stripes-connect will generate a JS alert when it encounters a 4xx or 5xx response, as in the screenshots in https://folio-org.atlassian.net/browse/CIRC-1349#icft=CIRC-1349. But devs have the option to set throwErrors: false which essentially tells stripes-connect "I'll handle this; don't send that alert." The bug here is that instead of silencing stripes-connect and then handling the error, some resources silence stripes-connect and then ignore the error.

Just checking @Zak Burke: The error message that once see e.g. in this bug https://folio-org.atlassian.net/browse/CIRC-1349#icft=CIRC-1349 (see the screenshots) is NOT what you're describing in this bug?