After upgrading my test version from 3.22.2 to 16.5.5.1 I observed problems when searching patrons. These problems were not visible when using MS-IE11. However normally I am using Firefox(50.0.2) and the following problems are observed: Giving the patrons full cardnumber (barcode) : ok, everything is fine. Giving a substring of username or cardnumber : no success (even the small pop-up "loading" doesn't show. Choosing the start letter of the username: no success.
Problem continues to exist after upgrading to koha stable (16.11.0).
Problem doesn't exist when tested from another laptop (windows 10, also Firefox 50.0.2). This suggests the problem is a problem with the laptop and not with koha. I will try to give more details as soon as available.
clearing the cache (Firefox options Advanced: Cached Web Content"clear now" has solved the problem.
Apparently wrong content was cached by Firefox. This resulted in apparent function failure. Conditions for caching such wrong content are unknown. I can not reproduce the incorrect behaviour. Just in case some one else runs into a similar problem: clearing the cache may solve your problem.