Hide softkey feature in Galaxy S8 leads to input lag when trying to receive input into text box.

Hide softkey feature in Galaxy S8 leads to severe lag/freeze when trying to insert character into textbox in UMG.

This feature is updated for Global version(Mali) for now(7/24/17) So you might need this version to reproduce.

This issue is reproduced in either improved virtual keyboard is enabled/disabled.

Workaround: check the "Enable Fullscreen Immersive on KitKat and above devices" under Project Settings, Android. With this setting, the issue does not occur.

1) Create an widget with text box(multi-line)
2) Save Widget
3) Add a script to add this widget when game is started.
4) Run project in Galaxy S8(Mali, Global version)
5) Touch textbox
6) Try type in any characters
Notice that there's no lag at all
7) Try swipe from rightmost outside frame to inside
8) Select dotted button from swipe menu to hide softkey(toggle)
9) Select textbox
10) Try input any characters

Expected: characters are inserted without latency
Result: No characters are inserted with severe latency, freezing.

Samsung S8+ Virtual Keyboard Fullscreen