JQL search panel is missing when viewing saved filter due to missing Tomcat parameters

Summary

JQL search panel is missing when viewing custom filter.

Symptoms

<Jira>/rest/api/2/filter/favourite?expand=subscriptions[-5:] endpoint responds with http code 400

Steps to reproduce

1. Install Jira 7.12.2
2. Create sample project
3. Save filter with any JQL
4. Go to saved filter

Expected result

Page shows JQL on top of the issue list and issue view

Actual result

JQL panel is missing.

Workaround

1. Open configuration file server.xml (should be in conf directory)
2. Find all connectors your application is using
3. Add relaxedPathChars="[]|" relaxedQueryChars="[]|{}^\`"<>" to properties for example: 

   <Connector port="8080" relaxedPathChars="[]|" relaxedQueryChars="[]|{}^&#x5c;&#x60;&quot;&lt;&gt;" maxThreads="150" minSpareThreads="25" connectionTimeout="20000" enableLookups="false" maxHttpHeaderSize="8192" protocol="HTTP/1.1" useBodyEncodingForURI="true" redirectPort="8443" acceptCount="100" disableUploadTimeout="true" bindOnInit="false"/>

4. Restart Jira
   See KB for full details: changing server.xml to handle requests with special characters

If you have multiple connectors in Jira, add the new parameters to each connector.

Notes

Cause of the issue is new version of Tomcat (8.5.32) which was updated in 7.12.2.