Suckless' tabbed integration with BSPWM. This configuration supports joining any two neighbouring windows into a new tabbed, removing windows from tabbed and when last window is from tabbed removed then tabbed instance is closed. This slightly modified `tabc.sh` allows to omit id of the removed window (the current one is removed by default).

sxhkdrc

# Remove current tab from tabbed
super + mod1 + t; r
        tabc.sh $(bspc query -N -n focused) remove

# At given direction: join two windows into a new tabbed or add window to an existing tabbed
super + mod1 + t; {Left,Down,Up,Right}
        tabc.sh $(bspc query -N -n {west,south,north,east}) add $(bspc query -N -n focused)

tabbed_slash_config.h

#define MODKEY Mod4Mask
static Key keys[] = {
        /* modifier             key        function     argument */
        { MODKEY|Mod1Mask,     XK_Return, focusonce,   { 0 } },
        { MODKEY|Mod1Mask,     XK_Return, spawn,       { 0 } },

        { MODKEY|Mod1Mask,           XK_Next,  rotate,  { .i = +1 } },
        { MODKEY|Mod1Mask,           XK_Prior, rotate,  { .i = -1 } },
        { MODKEY|Mod1Mask|ShiftMask, XK_Prior, movetab, { .i = -1 } },
        { MODKEY|Mod1Mask|ShiftMask, XK_Next,  movetab, { .i = +1 } },

tabc.sh

#!/bin/sh

# Usage:
# tabc.sh <tabbed-id> <command>
# Commands:
#    add <window-id> 	- Add window to tabbed
#    remove <window-id> - Remove window from tabbed
#    list		- List all clients of tabbed

TABBED_CONFIG="-c -k -o #111111 -O #7A7777 -t #8F8E24 -T #FFFFFF"

#
# Functions
#

# Get wid of root window
get_root_wid () {
	xwininfo -root | awk '/Window id:/{print $4}'
}

# Get children of tabbed
get_clients () {
	id=$1
	xwininfo -id $id -children | sed -n '/[0-9]\+ \(child\|children\):/,$s/ \+\(0x[0-9a-z]\+\).*/\1/p'
}

# Get class of a wid
get_class () {
	id=$1
	xprop -id $id | sed -n '/WM_CLASS/s/.*, "\(.*\)"/\1/p'
}

#
# Main Program
#

tabbed=$1; shift
cmd=$1; shift
if [ "$(get_class $tabbed)" != "tabbed" ]; then
	# It looks like what supposed to be an id of a tabbed window is not a
	# tabbed.
	if [ $cmd = "add" ]; then
		# But this is the `add` command so lets join booth windows in a
		# new tabbed instance. First start tabbed, add the target window
		# and then proceed to normal `add`.
		sibling=$tabbed
		tabbed=$(tabbed $TABBED_CONFIG -d) && xdotool windowreparent $sibling $tabbed || exit 2
	else
		# For other commands we need tunning tabbed instance
		echo "$tabbed is not an instance of tabbed"
		exit 1
	fi
fi


case $cmd in
	add)
		wid=$1; shift
		xdotool windowreparent $wid $tabbed
		;;
	remove)
		wid=$1
		# When there isn't supplied an id of a window to be removed
		# from tabbed then remove the currently active one.
		test -n "$win" || wid=$(get_clients $tabbed| head -1)
		xdotool windowreparent $wid $(get_root_wid)
		;;
	list)
		get_clients $tabbed
		;;
esac

I do not understand the purpose of tabbed_slash_config.h, I could imagine placing it into the source code and do make install and somehow something would be added/facilitated, but that's all.

Sorry maybe I should explain it better. It's tabbed/config.h (gist file names can't contain /, that's why you see _slash_).
So you should put or rather replace part of config.h in tabbed's source code. Tabbed follows suckless philosophy and to change it's configuration you have to edit and recompile code.

Do I need to modify the make file?

No.

License for above code is MIT (https://mit-license.org/).

Thank you! Sorry I deleted my comment, I noticed this isn't actually the upstream so I assume tabc.sh is under whatever license jpentland chooses (assuming there is license and the license wants derivatives to share alike).