An issue in the "An introduction to regular expressions" course by Andrew.1993

Hi all,
I would prefer to contact the creator directly for this issue, but anyways.
It seems that there is an issue while TYPING expressions like \d, \s, \D, \S. The answer is always marked with a yellow color and is regarded as erroneous. I even copy paste the correct answer from the suggested correct answer of the exercise, but to no avail. This hinders seriously the proceedings of the course as the course algorithm seems to get stuck and keeps on asking for TYPING the correct answer.
Any comment from the creator would be highly appreciated.
Cheers,
Theofilos

I’m having the same problem on this same course - its also occurring on another computing course:

Is it another problem with how Memrise are now handling punctuation marks ?