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lib/ExpensiMark.js

@@ -282,6 +282,15 @@ export default class ExpensiMark {
                     return `<blockquote>${isStartingWithSpace ? ' ' : ''}${replacedText}</blockquote>`;
                 },
             },
+            /**
+             * Use \b in this case because it will match on words, letters,
+             * and _: https://www.rexegg.com/regex-boundaries.html#wordboundary
+             * The !_blank is to prevent the `target="_blank">` section of the
+             * link replacement from being captured Additionally, something like
+             * `\b\_([^<>]*?)\_\b` doesn't work because it won't replace
+             * `_https://www.test.com_`
+             * Use [\s\S]* instead of .* to match newline
+             */
             {
                 name: 'italic',
                 regex: /(<(pre|code|a|mention-user)[^>]*>(.*?)<\/\2>)|((\b_+|\b)_((?![\s_])[\s\S]*?[^\s_](?<!\s))_(?![^\W_])(?![^<]*>)(?![^<]*(<\/pre>|<\/code>|<\/a>|<\/mention-user>)))/g,