[Koha] OPAC display "double vision"

[Paul]

For just a very few of our holdings (and so far we haven't found a pattern 
for the behaviour), we are getting a "double vision" effect in Firefox, 
Chrome, Opera so it doesn't seem to be browser specific.

The book/item is found without problem, but just under the "Holdings - 
Title notes - Comments" tabs, it starts a new "page" with "No results 
found!"  As soon as you click on any of those tabs, the "double" disappears 
... but "reload" brings it back ...

For an example please see <http://navalmarinearchive.com/ims/opac_double.jpg>

Has anyone else ever noticed this behaviour in Koha 3.8.x?

Many thanks -- and for Canadians, Happy Thanksgiving Day.

Paul