Issue loading is slow on Customer Portal if the issue has many attachment thumbnails

14-Nov-2019 13:52:08.711 WARNING [ContainerBackgroundProcessor[StandardEngine[Catalina]]] org.apache.catalina.valves.StuckThreadDetectionValve.notifyStuckThreadDetected Thread [http-nio-8080-exec-2113] (id=[459557]) has been active for [124,474] milliseconds (since [11/14/19 1:50 PM]) to serve the same request for [https://jira.sample.com/servicedesk/customershim/secure/thumbnail/314628/_thumb_314628.png?fromIssue=276371] and may be stuck (configured threshold for this StuckThreadDetectionValve is [120] seconds). There is/are [1] thread(s) in total that are monitored by this Valve and may be stuck.
 java.lang.Throwable
	at java.util.regex.Pattern$CharProperty.match(Pattern.java:3779)
	at java.util.regex.Pattern$Curly.match0(Pattern.java:4262)
	at java.util.regex.Pattern$Curly.match(Pattern.java:4236)
	at java.util.regex.Pattern$Ques.match(Pattern.java:4184)
	at java.util.regex.Pattern$Curly.match0(Pattern.java:4274)
	at java.util.regex.Pattern$Curly.match(Pattern.java:4236)
	at java.util.regex.Pattern$BmpCharProperty.match(Pattern.java:3800)
	at java.util.regex.Pattern$GroupHead.match(Pattern.java:4660)
	at java.util.regex.Pattern$Branch.match(Pattern.java:4606)
	at java.util.regex.Pattern$Start.match(Pattern.java:3463)
	at java.util.regex.Matcher.search(Matcher.java:1248)
	at java.util.regex.Matcher.find(Matcher.java:637)
	at com.atlassian.servicedesk.internal.feature.customer.request.CustomerViewableAttachmentService.lambda$isAttachmentInlinedInMarkup$3(CustomerViewableAttachmentService.java:100)
	at com.atlassian.servicedesk.internal.feature.customer.request.CustomerViewableAttachmentService$$Lambda$7516/644366677.test(Unknown Source)
	at java.util.stream.MatchOps$1MatchSink.accept(MatchOps.java:90)
	at java.util.ArrayList$ArrayListSpliterator.tryAdvance(ArrayList.java:1359)

UPDATE fileattachment set thumbnailable = 0 where issueid = xxxxx