Widgets should pop at the bottom of the analysis page

**Is your feature request related to a problem? Please describe.**
I have to scroll at the top of the screen and drag the widget at the bottom each time I add a widget.

**Describe the solution you'd like**
The widget pops at the bottom of the analysis page and the screen scrolls to it

**Describe alternatives you've considered**
- A popup ask for where to place the widget
- The widget is placed near where the focus is

**Additional context**
Also provide infinite scrolling?