Web selections not applied / As if webpage loses focus

[#1]

Dear community,

I'm experiencing a situation at client site where sometimes selections made (in listbox or multibox) are not being applied.

If done from multibox, the list stays opened even after finishing selecting the desired values.

Selections being made don't appear in the current selections.

It seems as if the webpage is losing focus, hovering over the multibox and mouse-scrolling to activate it and view the different fields added, doesn't take effect anymore.

I should click on the up/down arrows to be able to scroll and even in this case the selections are not applied as I described above.

We're using the IE plugin.

QV Version 11.20.11922 - WinServer 2008 R2.

Did anyone experience such a behavior ?

Appreciate your input and suggestions.

Regards,

JP

[#2]

Additional info:

This issue is raised on IE9 and IE10.

IE8 seems to work fine as well as full browser.

Any hint ?

Thanks.