Some extra characters are added to the site url (which is under development.concrete5 cms is used). There was no such problem before.
#.UHVsDy7Mja9
Is added at the end of every url after loading the page. I have checked the htaccess, header and footer, but can't find any unwanted code there. Is it a spam?
Although there are probably other "plugins" that do that, a possible candidate is AddThis (if you are using that of course).
AddThis adds a hash-tag to the end of every url for tracking purposes but it can be turned off using (in javascript):
var addthis_config = {"data_track_addressbar": false};