I had this issue on Windows 10 in the 1.10.0 release, but have yet to attempt reproducing. The ender dragon was summoned in a flat creative overworld with /summon. Target selectors did not seem to work on it as I tried both /kill @e and /tp @e 0 -50 0 and the ender dragon was not listed in the results. Oddly the trident damaged it although other weapons did not.
I had this issue on Windows 10 in the 1.10.0 release, but have yet to attempt reproducing. The ender dragon was summoned in a flat overworld with /summon. Target selectors did not seem to work on it as I tried both /kill @e and /tp @e 0 -50 0 and the ender dragon was not listed in the results. The trident did work however as said above.
You can change the sensitivity under Settings > Controller > Sensitivity.
I've noticed this seems to happen only after clicking the slash button.
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