In order to use redshift you need to know 3 tips

Redshift had been deleted from the iso in the past because it did not work. As of 19.03 version it is back on the iso and it includes a fix.

People who stay rolling install it like this

sudo pacman -S redshift

Tip 1 :

Make sure /etc/geoclue/geoclue.conf contains these lines at the bottom (starting from 19.03 it is present)

[redshift]
allowed=true
system=false
users=

 

Tip 2 :

Launch redshift the first time in a terminal. This applies to all users!

You hardly see the effect of redshift in the video if at all.

Check your own systems at daybreak, nightfall and at night.

Tip 3 :

If you use HBLOCK then remember to check if you deleted the hashtag in front of

/etc/hblockd/whitelist.list

location.services.mozilla.com