There are a couple of places where a popup blocker can stop an action in the web client. When adding a copy or viewing report output, the editor or output opens in a new tab, which can be blocked by the browser.
Although we can inform users when they first start using the web client that they should allow popups from their Evergreen domain, this step is easily forgotten when new computers are purchased or the settings are otherwise cleared from the browser. This can then lead to frustration when the user can't figure out why they are no longer able to add an item - the popup alert from the browser isn't very noticeable.
I've noticed other sites sometimes provide a friendly alert when a popup is blocked, informing the user that it appears the browser has prevented the window from opening and advising the user to allow popups for the site. It would be nice to have a similar alert in the web client for those actions that can be prevented by popup blockers.
Confirmed; especially with popup blocking being the default on Chrome, a notification to disable the blocker would be excellent.