I am searching through the problems for a specific tag. I want them to be sorted by problem number. A day or so earlier, they are indeed nicely sorted by problem number. Right now it doesn't seem to be sorted. Is this a bug or intended change? If so please consider adding the feature to sort by problem number.
Here is page 10 of constructive algorithms retrieved as I wrote this. Link Filter by Constructive Algorithim
Not all tags are affected. For example, the divide and conquer tag is sorted. This is also how I expect it to work.
This is an important feature: I plan to do only early problems with tags shown and save recent problems for virtual contests.
EDIT: I got so annoyed by this that I just wrote my script and use codeforces API instead... Script