I checked, some other members were receiving the same email last December. I found some screenshots. This progress bar will do nothing. It's just a bar with two dates. On the left the date IRCC received your application, on the right the estimation date based on their current estimated processing time (which is now 12 months).
So you will see "Dec 03, 2018" on the left and "Dec 03, 2019" on the right. And in between will be "the progress" if you can call it like that, just based on time passed since Dec 03.
Here's quotation from there website:
The progress bar shows how long it may take to process your application. The bar and estimated dates are based on the date we received your application and our processing times. It isn’t based on your application’s progress.
In other words, it's totally useless.