Updated description by Jarl-Penguin:
Summary:
The sneak button flickers when touching the left side of the screen with Lefty and Swap Jump and Sneak options enabled.

Steps to reproduce:

1. Enable Lefty and Swap Jump and Sneak options.
2. Touch the left side of the screen.

Observed results:
Sneak button flickers.

Expected results:
Sneak button doesn't flicker.

Original description:
The sneak button disappear when using (lefty) and (swap jump and sneak) settings and touching or moving the left corner