Breaking escape codes in combination with neovim

[tu500]

First of all, thanks for being my terminal emulator of choice and seemingly the only one with working pseudo-transparency support. Now to the point:

For several versions my neovim has been acting weird, printing jumbled characters upon certain actions, see screenshot.

As this does not happen with any other terminal emulator I've tried, I think this problem lies somewhere with lilyterm, though I'm not sure about that. I have bisected neovim and found that this behaviour started with this commit. So apperently, since neovim started correctly parsing terminfo.

I'm using a Fedora 28 and using a lilyterm git build and a vanilla (plugin-free) neovim does not help. Some other info:

$ lilyterm -v
LilyTerm 0.9.9 (2017-08-03)
$ echo $TERM
xterm-256color
$ echo $termcap

$ uname -a
Linux 4.17.3-200.fc28.x86_64 #1 SMP Tue Jun 26 14:17:07 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

I have no idea how to debug this further, but if any other info is needed just ask.

Thank you.

[egmontkob]

The escape sequence that appears on the screen is ESC followed by 2 q or 6 q. These sequences switch the cursor shape.

Lilyterm can use GTK+ v2, and in turn VTE 0.28 for terminal emulation. This version of the terminal emulation library is 7 years old, contains plenty of known bugs and lacks many new versions including this one, and is no longer maintained. This old VTE behavior won't be fixed, and unless you feel like fixing it for yourself, all you can do is configure neovim not to emit these codes.

Or Lilyterm can use GTK+ v3, and in turn the newest and actively maintained VTE (0.54 being the newest currently) which already supports switching the cursor shape using these escape sequences, plus plenty of other new features and improvements. It no longer supports pseudo-transparency, though.