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Body Expressions are required to match the line of text that prefixes 'replied to' content. This content varies depending on the email client used and the locale of the client user. Effectively it is just text so we must match it as closely as possible. As mentioned above ALL delimiter expressions are evaluated with a \n prefixing them to minimize the number of matches. This also works at the start of the email content as \n is dynamically injected for that case, and removed after. Its better to range match on expected text than take the 'lazy' .* route, bad regexps that overuse .* can cause A LOT of possible match evaluations by the Regexp Engine. If your Jira stops processing mail, one possible causes is an overuse of .*, the Regexp Engine is busy, it could take a few hours, days or longer to complete owing to the combination of Regexp and email size.
HTML To Wiki Markup
HTML Email can be covered to wiki markup via JEMH. However, wiki markup uses additional characters to define styling. Such as text that is formatted in a bold HTML tag,when covered to wiki markup the bold HTML tag is removed and text will instead have * placed around it (wiki markup bold formatting).
As seen in this example:
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Because wiki markup uses these characters for styling your Regexp will need to account for these characters, both when they are, and when they are not present. The following link will give more details on the extra characters added by wiki markup:
https://jira.atlassian.com/secure/WikiRendererHelpAction.jspa?section=all
Some of theses characters are special in Regexp such as the * and [ ]. So in order for Regexp to specifically match these special characters as text, you need to escape them by using a back slash \ before the special character. See following link for a tutorial and a example:
https://regexone.com/lesson/wildcards_dot
The easier way
With the above in mind, you’re Regexp maybe longer and more complicated to write. The alternative approach you could take is turning off which HTML elements are handled via JEMH. If you go to:
JEMH > Profile > Email > HTML
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The HTML elements you have switched On will be formatted to markup, which means JEMH will add extra characters to handle these tags. If you no longer want that specific tag to be formatted you can simply switch it to None. This will result in issues no longer having styling for those elements. For example: if the bold and link tags were both switched to None, issues would no longer display bold text and hyperlinks. However, this does mean that the Regexp you have to write will be smaller / easier to write.
Dynamic Evaluation walk-through
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