Design view adding object work not as expected

Wappler Version :2.5.5
Operating System :Mac OS 10.15.2

Expected behavior

What do you think should happen?

Creating a new page with all frameworks loaded. Clicking the PLUS to add container, Clicking the PLUS to add ROW, clicking the PLUS to add column

Actual behavior

After creating container the PLUS give sometime the option for a row, sometime no option for row. Same with columns, or after creating column, no plus available to add another column.
It feels very unsupportive!

How to reproduce

See the above steps.