Desktop hang with LO 5.05 Calc flyover help

I had a desktop hang using LO Calc 5.05 running under Redhat EL5.

I was adding a borders on multiple rectangles using the tools in the right sidebar.
When I selected the “Thick Box Border” the flyover help for the “Thick box border” appears, if you then mouse up to the right slightly the neighboring “Select the line color of the borders” flyover pops up and starts flashing rapidly.

At this point the entire desktop is hung and I cannot get anything to stop it.
The only recovery I found was to switch to the 1st terminal and kill soffice.

To avoid the problem I made the sidebar wider so there was no accidental hover-over clash,

Anyone else see this?