I've never liked how calculation manager and various other EPM links open in pop up windows rather than tabs. Recently I hit that level of annoyance or boredom where I was actually bothered to do something about it so a quick search uncovered that it is quite easy to deal with in Chrome and the new Edge. There are options in Firefox as well but not so simple.
So next time you, for example, open Rules in PBCS and it opens up in a pop-up, simply right click in the title bar and click 'Show As Tab'. You'll then have a regular tab window that you can drag back to whatever main window you want.
You will then have the satisfaction of some nice neat tabs... which if you're anything like me will be alongside those other 100 tabs you seem to have open for a rainy day.
As mentioned above this works exactly the same in Edge, I guess since its based on Chromium. As for Firefox it is not so simple. I don't think there is a way for you to do this individually or on demand. It sounds like the only way is to permanently configure all popups to open as new tabs . This may or may not be what you want but if it is take a look at the solution in this link.