Thank you @dennis77 and @Marius for confirming this on your ends.
I have also noticed that Safari displays a different read time to the other browsers.
Interestingly, on my own installation, the read time remains consistent, regardless of the browser used.
To investigate this further, I have set up a demo instance.
Please log in with this, and see the Single Posts template and Read time test post.
Feel free to play around, to see if the error is reproducible.
Hey @Araminta, thanks for taking the time to setup the sandbox environment.
After doing some more debugging, I’ve noticed that it’s a conflict with WP Rocket causing the issue. When disabling WP Rocket’s image lazy loading, the reading times are consistent.