work for me.  Moved back to $mod+Return (for example) for terminals etc.
Custom shortcuts (e.g. $mod_next+i etc.) remains though.
Cleaned up some unused keyboard shortcuts.

having this since work env is impacted by this).

application management $mod_next.  Changed quitting application to
$mod_next+q: Terminal is now $mod_next+Enter, and so on.

(https://github.com/sagb/alttab) and can't grab Alt+Tab hjkl since i3
has grabbed them.  Rofi does work in this case though.

skippy bindsyms.  Changed rofi and application shortcut keys to Super.

Clash with my container container focusing keys ($mod+Ctrl+hjkl) so
disabled container focusing in i3.

was interfering with vim (for example undo changes etc).  Disabled alsa
audio (was cntrl+alt).

necessitates using Mod1 so have gotten used to that.

$mod+z|x splits horizonal/vertical. Added README.md.

disabling some client.x theming/colouring.

99ppt and 1ppt (essentially "hides" the other window - although see a
small sliver to remind you some windows are there).

Changed predefined size for horizontal window split (from 90/10 to 70/30) for shortcuts $mod+Mod1+u,i,o.

Added special full screen floating mode (i3 fullscreen has slight transparency with chromium video that I don't like).

Setting custom x11 property on windows to disable dimming (anti-dim) on active window with mod+Mod1+a for anti-dim model and mod+Mod1+d for dim mode.

Moving from inactive-opacity to inactive-dim.  Mark sticky windows with always focused (never dims).