Backspace broken when using HeliBoard keyboard

[ducklin5]

Describe the bug
HeliBoard + AcodeX: after recalling command history with the Up arrow, I'm unable to backspace any of the recalled characters.

The same workflows work correctly with: HeliBoard + Termux and Gboard + AcodeX
So this appears to be a compatibility problem between AcodeX’s input handling and HeliBoard’s Input behavior.

To Reproduce
Steps to reproduce the behaviour:

0. Enable heliboard keybaord
1. In AcodeX terminal: Type a command (e.g. echo test) and press Enter.
2. Press the Up arrow in the terminal to recall the previous command.
3. Try to use Backspace to edit the recalled command.
4. Optionally: type some characters, switch to another keyboard (e.g. Gboard), then switch back to HeliBoard, and try to backspace again.

Expected behavior
Backspace should remove all characters that can be remove from the terminal

Smartphone

• Device: POCO F4 GT
• OS: Android 14
• Keyboard: HeliBoard (v3.6 from Helium314/HeliBoard)
• Termux: googleplay.2025.10.05
• Acode Version: v1.11.7
• AcodeX version: v3.2.0

Additional context
Other combos tested:
HeliBoard + Termux → OK
Gboard + AcodeX → OK

When typing 2 characters very quickly (e.g. f and k), the terminal often shows ffk instead of fk.

If I then press Backspace:
    I can only delete the last 2 characters (fk),
    The first f is “stuck” and cannot be deleted with Backspace.

[bajrangCoder]

Actually AcodeX terminal uses webgl for rendering and input handled through server and xterm. There is no intermediate things like textarea etc. and it follows standard key stuff.

Also it already works perfectly with Gboard, others keyboards and this heli board is a exception (i hadn't seen this before )

Your suggested fix isn't even possible.

[ducklin5]

Actually AcodeX terminal uses webgl for rendering and input handled through server and xterm. There is no intermediate things like textarea etc. and it follows standard key stuff.

Also it already works perfectly with Gboard, others keyboards and this heli board is a exception (i hadn't seen this before )

Your suggested fix isn't even possible.

Apologies. I hoped copilot would be able to find the general area of the cause.
Definitely wont be trusting github copilot for issue reports again.

I've update the initial issue just to indicate the behaviour that I'm seeing.

And having tested again, I've also noticed that its happening in the regular Acode terminal as well.
So perhaps this is Acode/Heliboard bug after all and not specifically for AcodeX.
I'll figure out which repo the issue should really go to.

This issue can definitely be closed if there is nothing to be done from this repos side.

[bajrangCoder]

@ducklin5 Both Acode and AcodeX uses same terminal library i.e xtermjs(which is used in vscode).