use non-greedy match for capturing mentions
diff --git a/migration/src/jira_util.py b/migration/src/jira_util.py
index 505a336..69f919d 100644
--- a/migration/src/jira_util.py
+++ b/migration/src/jira_util.py
@@ -228,8 +228,8 @@
REGEX_CRLF = re.compile(r"\r\n")
REGEX_JIRA_KEY = re.compile(r"[^/]LUCENE-\d+")
-REGEX_MENTION_ATMARK = re.compile(r"(^@[\w\.@_-]+)|((?<=[\s\(\"'])@[\w\.@_-]+)(?=[\s\)\"'\?!,;:\.$])") # this regex may capture only "@" + "<username>" mentions
-REGEX_MENION_TILDE = re.compile(r"(^\[~[\w\.@_-]+\])|((?<=[\s\(\"'])\[~[\w\.@_-]+\])(?=[\s\)\"'\?!,;:\.$])") # this regex may capture only "[~" + "<username>" + "]" mentions
+REGEX_MENTION_ATMARK = re.compile(r"(^@[\w\.@_-]+?)|((?<=[\s\(\"'])@[\w\.@_-]+?)(?=[\s\)\"'\?!,;:\.$])") # this regex may capture only "@" + "<username>" mentions
+REGEX_MENION_TILDE = re.compile(r"(^\[~[\w\.@_-]+?\])|((?<=[\s\(\"'])\[~[\w\.@_-]+?\])(?=[\s\)\"'\?!,;:\.$])") # this regex may capture only "[~" + "<username>" + "]" mentions
REGEX_LINK = re.compile(r"\[([^\]]+)\]\(([^\)]+)\)")
