This one single method will work in both 64bit and 32bit systems by using the 32bit flash natively, or emulating it. Either way, it uses nspluginwrapper, which will pull in a lot of libraries (packages), but most of them should be quite small. You can download and execute this file or just copy and paste the whole block into your terminal, then …

install_flash_for_midori.sh

clear &&
echo 'Installing Flash for Midori' &&
read -p 'Press Enter to continue, or abort by pressing CTRL+C' nothing &&
mkdir -p ~/.mozilla/plugins &&
wget https://fpdownload.adobe.com/get/flashplayer/pdc/11.2.202.626/install_flash_player_11_linux.i386.tar.gz &&
tar -zxvf install_flash_player_11_linux.i386.tar.gz libflashplayer.so &&
rm install_flash_player_11_linux.i386.tar.gz &&
if [ $(getconf LONG_BIT) = '64' ]
then
	mv libflashplayer.so ~/.mozilla/plugins/libflashplayer.32.so &&
	sudo apt install nspluginwrapper:i386 libnss3:i386
else
	mv libflashplayer.so ~/.mozilla/plugins/libflashplayer.so &&
	sudo apt install nspluginwrapper
fi &&
nspluginwrapper -a -v -n -i

OK, HOW do I undo this it installed like 200 packages, an entire 32 bit Linux installation on top of my 64 bit installation. I know that there is no way just installing flash needs all of these i386 files. Thai language support library, QT, esd ????

Midori requires a 32bit version, so it does.

Use https://www.adobe.com/uk/software/flash/about/ to check.

The link is broken...

Connecting to fpdownload.macromedia.com (fpdownload.macromedia.com)|95.100.2.70|:80... connected.
HTTP request sent, awaiting response... 404 Not Found
2014-12-12 10:42:04 ERROR 404: Not Found.

Just download the .tar.gz archive manually into the folder of your midori-flash script (the script above copied and saved as midori-flash.sh e.g.), and edit the following line as below:

# wget http://fpdownload.macromedia.com/get/flashplayer/pdc/11.2.202.378/install_flash_player_11_linux.i386.tar.gz &&

Important: on the download site click "i need flash for another computer" and choose linux 32 bit, then the .tar.gz Version.

link should now be http://fpdownload.macromedia.com/get/flashplayer/pdc/11.2.202.442/install_flash_player_11_linux.i386.tar.gz

You need to update the wget command for current version: https://get.adobe.com/flashplayer/

As shown for version 11.2.202.569 current to date on this fork: https://gist.github.com/TomKellyGenetics/2210a5aa0ccf603d5f58

Updated to 11.2.202.626