Well, for me it started after updating on 4.2 (which I am still on). No keyboard patches and few apps installed here. I do not think it depends on your doing 
I am not aware of a permanent fix but as a temporary workaround I use the solution posted by @peterleinchen
systemctl --user restart maliit-server
After I used it once, whenever the bug represents itself I shoot up the terminal and press the the ‘up’ arrow to evoke recent commands (which is handy as the bug occurs quite often, every two days or so).
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