You might try working from the Live View Editor. It's a little different while working with tables, but the pop-up won't show.
To activate Live View's table mode...
1. Click the upper left corner of your layout table to get the blue table tab to appear.
2. Click the "hamburger menu" in the table tab to make a black highlight appear around your cells
3. From there, you can merge/split/add/remove by right clicking and choosing from the list
Otherwise, just select items so a blue highlight appears to edit them. Text can be a little more tricky, requiring a double click in CC2019. CC2020 is much better to work with in the Live View Editor, but don't allow it to remove older versions when you install. That way you can keep the familiar versions while learning the nuances of the new one.