Think of it this way: each time you open a Bubble tab in your browser, it’s downloading a copy of your app. Certain aspects are updated across browser tabs automatically. However, something like a reusable element or field, when created/deleted on one tab, is not going to reflect automatically in the other.
I can’t give a definitive answer. But I definitely recommend doing so sparingly. (Ie. good when you’re referencing another page). And never work on the same page simultaneously in different tabs.