Tripple opt-in/out, event preview and optional registration until end date

[FEATURE] Add optional verification step for confirm and cancel registration #1237

This feature allows to optionally add an additional verification step, when a user confirms or cancels a registration. When enabled, confirmation- or cancellation-links will lead to a page, where the user has to manually confirm the confirmation- or cancellation.

This feature is useful, when Email Security Gateways or Antivirus/Anti-Malware Software scan registration emails and follow confirmation- or cancellation-links, leading to unwanted confirmation or cancellation of an event registration.

[FEATURE] Allow preview of event records #988
[FEATURE] Optionally allow registration until event end date #1235
[TASK] Provide 5th argument for BackendUtility::wrapClickMenuOnIcon #1232
[TASK] Remove outdated langDisable in FlexForm #1230
[TASK] Do not send emails with empty subject #1234
[TASK] Avoid usage of deprecated internal_type in FlexForm #1236
[TASK] Avoid usage of deprecated array keys in FlexForm #1236
[TASK] Use mailpit instead of mailhog in acceptance tests #1241
[DOCS] Add how to deactivate email notifications to the FAQs #1239 - thanks @h-e-l-l-o-w-o-r-l-d

Optional registration until end date

[FEATURE] Optionally allow registration until event end date #1235
[TASK] Do not send emails with empty subject #1234

Bugfix release

[BUGFIX] Fixed calendar display issue for events on DST days #1219
[BUGFIX] Harden displayCond in event TCA #1220
[TASK] Remove "TCEforms" wrapper in FlexForm #1183

Bugfix release

[BUGFIX] Fixed calendar display issue for events on DST days #1219
[BUGFIX] Harden displayCond in event TCA #1220

Maintenance release

[FEATURE] Add body + subject to ModifyUserMessageSenderEvent - thanks @georgringer
[FEATURE] Added waitlist notification filter to backend module #1204
[BUGFIX] Allow backend module in all workspaces #1213
[TASK] Fix grammer issue #1211 - thanks @georgringer
[TASK] Provide additional variables in saveRegistrationResultAction #1210
[TASK] Exclude events without enddate from GDPR cleanup task #1215
[DOCS] Document e:uri.page ViewHelper #1212
[DOCS] Added name to identical confval anchors
[DOCS] Fixed Type confval

Maintenance release

[FEATURE] Add body + subject to ModifyUserMessageSenderEvent - thanks @georgringer
[FEATURE] Added waitlist notification filter to backend module #1204
[BUGFIX] Fix wrong check for waitlist moval #1198 - thanks @georgringer
[TASK] Provide additional variables in `saveRegistrationResultAction #1210
[TASK] Exclude events without enddate from GDPR cleanup task #1215

Bugfix and maintenance release

[FEATURE] Add content element wizard menu item #1199
[BUGFIX] Fix wrong check for waitlist moval #1198 - thanks @georgringer
[TASK] Add .gitattributes #1195
[DOCS] Switch Documentation Rendering to PHP - thanks @linawolf
[DOCS] Fixed wrong example TypoScript for attachments #1200
[DOCS] Add time_restriction to available display mode options #1184

Security Fix

[SECURITY] Fix broken access control in backend module 2e04c41
[FEATURE] Configurable default ordering in backend module #1169
[FEATURE] Allow attachments in custom notifications via TypoScript #1178
[BUGFIX] Fixed TypoScript for "Insert Record" event rendering #1180
[BUGFIX] Wrong hasMorePages item in pagination #1194
[TASK] Extend ModifyUserMessageAttachmentsEvent #1178
[TASK] Provide range for max fields #1181 - thanks @georgringer
[TASK] Include settings.singleEvent in FlexForm dataHandler hook #1187
[DOC] Fix typos #1192 - thanks @georgringer

Maintenance release

[FEATURE] Allow attachments in custom notifications via TypoScript #1178
[BUGFIX] Fixed TypoScript for "Insert Record" event rendering #1180
[BUGFIX] Wrong hasMorePages item in pagination #1194
[TASK] Extend ModifyUserMessageAttachmentsEvent #1178
[TASK] Include settings.singleEvent in FlexForm dataHandler hook #1187

Bugfix for disableOverrideDemand

[BUGFIX] ⚠️ Fix non-working disableOverrideDemand setting #1175 - thanks @SoraNoIseki

Important notice:
If filtering of events in list- or search-view does not work any more, please make sure to uncheck the "Disable overwrite demand" setting in the plugin.

[TASK] Use import for static helper functions in TCA overrides #1167
[TASK] Remove superfluous query condition in EventRepository #1173