Automated changelog update [skip ci]

CHANGELOG.md

@@ -6,10 +6,26 @@ The following sections list the changes for unreleased.
 
 ## Summary
 
+* Bugfix - Substring search for sharees: [#547](https://github.com/owncloud/ocis/issues/547)
 * Enhancement - Improve error log for "could not get user by claim" error: [#4227](https://github.com/owncloud/ocis/pull/4227)
 
 ## Details
 
+* Bugfix - Substring search for sharees: [#547](https://github.com/owncloud/ocis/issues/547)
+
+   We fixed searching for sharees to be no longer case-sensitive. With this we introduced two new
+   settings for the users and groups services: "group_substring_filter_type" for the group
+   services and "user_substring_filter_type" for the users service. They allow to set the type
+   of LDAP filter that is used for substring user searches. Possible values are: "initial",
+   "final" and "any" to do either prefix, suffix or full substring searches. Both settings
+   default to "initial".
+
+   Also a new option "search_min_length" was added for the "frontend" service. It allows to
+   configure the minimum number of characters to enter before a search for Sharees is started.
+   This setting is e.g. evaluated by the web ui via the capabilities endpoint.
+
+   https://github.com/owncloud/ocis/issues/547
+
 * Enhancement - Improve error log for "could not get user by claim" error: [#4227](https://github.com/owncloud/ocis/pull/4227)
 
    We've improved the error log for "could not get user by claim" error where previously only the