switching to an account with lot of contacts hang the ui for a few secs

Everything is in the title

changed milestone to %Itération 21

added SprintIn progress label

assigned to @ababi

added SprintTo review label and removed SprintIn progress label

mentioned in commit 69f5dfcd

removed SprintTo review label

closed

mentioned in issue #631 (closed)

mentioned in issue #718 (closed)

mentioned in issue #929 (closed)