Upper case non-ASCII characters rejected in verification question answers

[Sesquipedalian]

Description

If upper case non-ASCII characters are supplied in the answer to a verification question, the answer will be rejected even if it was correct.

Originally reported here.

Steps to reproduce

1. Include an upper case non-ASCII character in the accepted answer for a verification question.
2. As a guest, enter the exact same string when asked a verification question.
3. Note how the correct answer is rejected with an error message.

Environment (complete as necessary)

• Version/Git revision: f3b02b8
• Database Type:
• Database Version:
• PHP Version:

Additional information/references

The cause appears to be that we use $smcFunc['strtolower']() to convert the expected answer(s) to lower case, but plain strtolower() to convert the supplied answer to lower case. This means that upper case non-ASCII characters remain upper case in the supplied answer, and therefore that the comparison between the two fails.