If there is < in the question body and set minimum length to 100 then you get an error: please provide more information-At least 100 character.
to reproduce:
1. In admin/posting set Minimum length of question body to 100
2. choose markdown editor as your default editor
3. Ask a question with this text as the question body:
Let x<y and Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book.
3. Send the question
Now you see the error.