Pressing `<Del>` inserts unknown (unicode?) character; `<Pos1>` and `<End>` keys not working.

[dreirund]

Ahoj,

I built the (almost) latest state of this git repository (git commit hash: f751eb2 from 2026-05-27) using this recipe on Artix GNU/Linux (rolling release):

export RUSTUP_HOME="${srcdir}/.rustup"
export RUSTUP_TOOLCHAIN=stable
export CARGO_HOME="${srcdir}/.cargo"
export CARGO_TARGET_DIR=target

cargo fetch --locked --target host-tuple
cargo build --frozen --release --all-features

When I compose a message:

• <Pos1> and <End> keys do not work (cursor stays where it is),
• when I am in the middle of a text and press <Del>, instead of just deleting the next character some not-rendered (unicode?) character seems to be inserted in place of the character which is to deleted.
  Screenshots:
  1. Entered text -- cursor is between b and c:
     
  2. After pressing <Del>:
     
     (Yes, although it seems to be two characters: A box and a space, it behaves like one character (Moving the cursor passes through both the box and the whitespace).)

Regards!