It depends on which distribution.

In Slint with chromium provided by AlienBob:
wget http://the-brannons.com/kgejglhpjiefppelpmljglcjbhoiplfn.json
su
mkdir -p /usr/lib64/chromium/extensions
mv kgejglhpjiefppelpmljglcjbhoiplfn.json /usr/lib64/chromium/extensions/

Also, as a reminder, to allow ChromeVox to act as a client for
speech-dispatcher by default, edit /etc/chromium/00-default.conf so
the last line becomes:
CHROMIUM_FLAGS="$CHROMIUM_FLAGS --enable-speech-synthesis --enable-speech-dispatcher"

For the records, the json file is mentioned here:
https://chromium.googlesource.com/chromium/src/+show/lkcr/docs/accessibility/chromevox.md

The fist time you start chromium after a few seconds you should hear:
"ChromeVox spoken feedback is ready". 

link for the default shortcuts:
http://www.chromevox.com/keyboard_shortcuts.html

To access the Options tab before a ChromeVox key binding
be set:
F10 move the focus to Chromium options, then
Left arrow twice move the focus to a drop down menu for ChromeVox,
the second entry menu from the top is the Options tab, where
you can set the ChromeVox key binding.

You can change the voice from the ChromeVox Options GUI. 

I am saving this email for the Slint manual, yet to be written...

On 08/09/2018 02:19 AM, Jude DaShiell wrote:
> I had an e-mail message I think from you which gave the correct path 
for
> the chromium json file so chromium would come up talking and 
unfortunately
> lost that e-mail.  If you still have it in your archives please send 
that
> e-mail to me again.  I don't even know how an e-mail as important as 
that
> one is got lost on this end.