When composing a new tweet, replying to someone's tweet or composing a direct message (so very likely every 'compose' text field on Twitter), it's impossible to reposition the cursor anywhere except the end of the entered text. This is a bit frustrating when you spot a typo you made at the beginning of a long tweet :) master is unaffected. v1-trains and v1.0.1 are affected. noming as leo blocker as Twitter is one of the highlighted apps on the Firefox marketplace and a common usage of smartphones. I think it'd be an appropriate tef blocker, but I assume that only absolutely critical bugs (i.e. security/crashers) are being accepted at this stage(?) Uncertain what component this should belong too, quite probably a core bug?

Possibly related to Bug 802963 ?

I think this is a dupe of bug 814274.