Black bars appear in tmux sessions

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• iTerm2 version: Build 3.0.15

• OS version:10.12.3 (16D32)

• Attach ~/Library/Preferences/com.googlecode.iterm2.plist here (drag-drop from finder into this window) com.googlecode.iterm2.plist

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Detailed steps to reproduce the problem:

1. Open iterm2
2. Log into remote server
3. Attach to tmux session

What happened: unusable black space appears bottom and right of tmux windows

What should have happened: no black bar

This is because of tmux's requirement that all tabs have the same number of rows x columns (and spilt pane dividers count as 1 row or column in size). If you have only one pane per tab then you won't see this, but when you use split panes the usable space in tabs will differ.

This could also happen if you have two tmux clients attached with different maximum window sizes, but that is more unusual.

A couple of feature requests about this, in from easiest to hardest:

1. Make it possible to customize the colour of the filler space. If it was the default background color it would be less noticeable, (maybe it is customizeable, but it always seems to be darker than my terminal background)
2. More control of the split headers and borders so that they are as-wide-as-a-character to mirror the behaviour of terminal-mode tmux. (I can get someway there with disabling per pan title bars.

My goal would be to have it such that if I have only one client attached (iterm2) and have multiple windows, each with different split layouts (some horz, some vert) to not have the black borders show up. A simple repro layout:

tmux split-window -v && tmux new-window -t 1 && tmux split-window -t 1.0 -h

I'd settle for 1) so that I don't notice the difference in size as I jump between tabs.

changed milestone to %Review for next version

Solid idea, Ash. I'll keep this in mind.

Disabling per-pane title bars really helped to minimize the width/height of the black bar. I can live with that.

Settings > Appearance > Panes > Show per-pane title bar with split panes