I'm trying to run vim inside local tmux session. Vim on its own (both via terminal, and via gui with gvim) is working as expected. I'm running Debian stable, tmux 2.8, vim 8.1.549, urxvt 9.22.
The issue seems that screen isn't always being refreshed where it'd need to be. Particularly noticable when vim buffer gets bigger than screen size.
Scenario 1: simply opening vim.
Scenario 2: opening NERDTree in directory with many files
In tmux -- artefacts in main buffer. The file buffer shows wrong lines, as if they all were shifted. Notice how it lacks the "press ? for help" thing at top. The lines are refreshed to correct when go over them with the cursor (I pressed up and down a couple times in second screen shot)
Scenario 3: writting stuff to main buffer. I pressed 'a' and enter for couple seconds, then 'b' and enter for couple seconds, etc.
Also I made observation, that vim stuff leaks outside of tmux into my terminal's scrollback (ie I can see it when I've already exited tmux). Nothing similar happens when using vim without tmux.
My .Xresources file:
URxvt.font: xft:Monospace-10 URxvt.boldFont: xft:Monospace-10 URxvt.letterSpace: -1 URxvt.scrollBar: false !urxvt*termname: rxvt-unicode-256color !! ================== seoul256 ==================================== ! seoul256 (dark) theme adapted for URxvt URxvt*background: #3a3a3a URxvt*foreground: #d0d0d0 URxvt*color0: #4e4e4e URxvt*color1: #d68787 URxvt*color2: #5f865f URxvt*color3: #d8af5f URxvt*color4: #85add4 URxvt*color5: #d7afaf URxvt*color6: #87afaf URxvt*color7: #d0d0d0 URxvt*color8: #626262 URxvt*color9: #d75f87 URxvt*color10: #87af87 URxvt*color11: #ffd787 URxvt*color12: #add4fb URxvt*color13: #ffafaf URxvt*color14: #87d7d7 URxvt*color15: #e4e4e4 URxvt*cursorColor: #d0d0d0 URxvt*cursorColor2: #3a3a3a URxvt*colorBD: #e4e4e4
My tmux config
set -g default-terminal screen-256color