I have the exactly the same problem, i.e. messenger crashes the moment I try to type a message.
Other apps show weird behaviors too. This problem started on 4/24, Friday evening, after upgrades on a few things. But I think my phone got lollipop upgraded on an earlier date. anyhow, really terrible. the phone just doesn't work well, even after I tried to uninstall all upgrades to messenger itself. desperately need a fix or workaround
Yes, I did power the phone on and off.
Last evening, I believe I fixed it. I went in to the app manager and uninstalled the updates and reinstalled the app. It is working fine as of today.
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