Could you confirm that inactive (non-visible) browser tabs send requests as well? That shouldn't happen.
Jenkins 2.164.1 behaves correctly (tested with Chrome and Firefox): tabs that are not visible because they aren't selected, or the browser is minimised, do not generate Ajax requests. However, if the browser is fully obscured (with the tab selected), the requests (unsurprisingly) do get generated. We have a similar problem to Jochen Hinrichsen: users have browsers with the page selected (and then hidden behind either other browser windows, or things like IDEs) and the Ajax requests are hammering our Jenkins server. There is only so much resource we are willing/able to dedicate to this, and being able to increase the refresh interval would be a good way to immediately reduce server load. |