Hmm, I confess to be relying on this feature, because I thought it formed part of a wider (undocumented) "sticky locale" mechanism that this bundle uses; see #229 .

However, it's certainly the case that the stickiness is achieved through the use of the cookie alone (not, for example, the session var), which might indicate that the stickiness feature is not really intended; in which case the use of the cookie for the 'prefix' and 'prefix_except_default' strategies is indeed a bug.

[If the stickiness feature is intended, then I suggest using the session var for it as well, and then making the feature more configurable (including the ability to disable the use of the cookie); see my feature request at https://github.com//issues/230 .