Ajax not working properly after 7.19 update + migration

Hi,

Not sure the issue is core 7.19 related, as bug appends since update + migration.
Though, I saw many modules facing js bugs after 7.19 update, so i ask you guys if you have some clue about the following issue, which looks related to core js bahavior.

Context of bug:
1/ I had a multisite install on drupal 7.12.
2/ I updated the core to 7.19 and run update for 1 subsite without problem.
3/ I then migrated this site to a new server as a single main drupal site version 7.19. in hostpapa.
4/ I had to make 2 find-replace in the db.dump to adapt a/ full site url here and there (http://site1.com replaced by http://site2.com) and b/ to replace the relative path to files folder (sites/site1/files --> sites/default/files)

This migrated site works perfectly, except for the following bugs:
1/ drag 'n drop ordering not working.
2/ context UI is brocken: when you click on conditions or reaction, the js is not working and you can't do anything to contexts.
3/ For some Content type, CKEditor bar and buttons not loaded in nodes edition. (sorry i know it doesn't make sense but i checked the config and i can't tell what could trigger the bug...)

But drupal Chat, entity reference works properly for example.

I went to the update module page, it didn't tell me that my jquery version has to be updated.
But I had to update context to version 7.x-3.0-beta6, without solving the issue.

I attach the list of my modules to give the global picture.
Thanks in advance if you have some tips and/or directions for me to search the source of the issue.