Resolve "Fix displaying of messages in Vue frontend"

See merge request !1232

Merge branch '812-dynamic-routes-are-not-removed-in-frontend-immediately-when-they-are-removed-in-the-backend' into 'release-3.0'

Resolve "Dynamic routes are not removed in frontend (immediately) when they are removed in the backend"

See merge request !1227

Merge branch 'release-3.0' into '812-dynamic-routes-are-not-removed-in-frontend-immediately-when-they-are-removed-in-the-backend'

# Conflicts:
#   CHANGELOG.rst

Merge branch '833-progress-page-for-celery-tasks-doesn-t-show-error-messages-if-task-aborts-with-an-exception' into 'release-3.0'

Resolve "Progress page for Celery tasks doesn't show error messages if task aborts with an exception"

See merge request !1226

Merge branch 'release-3.0' into '833-progress-page-for-celery-tasks-doesn-t-show-error-messages-if-task-aborts-with-an-exception'

# Conflicts:
#   CHANGELOG.rst

Resolve "Remove vue_dummy"

See merge request !1224

Merge branch '838-offline-fallback-page-for-django-legacy-pages-is-misleading-in-some-situations' into 'release-3.0'

Resolve "Offline fallback page for django legacy pages is misleading in some situations"

See merge request !1225

Resolve "Authorized Applications spawns "mini-AlekSIS""

See merge request !1218

This reverts commit 0a8a214f.

Resolve "Regional tel format isn't accepted"

See merge request !1189

# Conflicts:
#   CHANGELOG.rst

Merge branch '814-changing-maintenance-mode-state-spawns-mini-aleksis-inside-aleksis' into 'release-3.0'

Resolve "Changing Maintenance Mode State spawns "Mini-AlekSIS" inside AlekSIS"

See merge request !1216

Merge branch '835-notifaction-send-always-creates-celery-task-with-force-sending' into 'release-3.0'

Resolve "Notifaction.send always creates Celery task with force sending"

See merge request !1212

Merge branch 'release-3.0' into '835-notifaction-send-always-creates-celery-task-with-force-sending'

# Conflicts:
#   CHANGELOG.rst

Resolve ""Retry" button opens about:blank in new tab"

See merge request !1220

# Conflicts:
#   CHANGELOG.rst

Merge branch '846-query-strings-do-not-get-passed-when-navigating-legacy-pages-in-spa' into 'release-3.0'

Resolve "Query strings do not get passed when navigating legacy pages in SPA"

See merge request !1222

Resolve "Fix cachalot issues (aka upgrade cachalot)"

See merge request !1221

Resolve "Move DeleteDialog from Plank to Core"

See merge request !1207

# Conflicts:
#   CHANGELOG.rst

Merge branch '838-offline-fallback-page-for-django-legacy-pages-is-misleading-in-some-situations' into 'release-3.0'

Resolve "Offline fallback page for django legacy pages is misleading in some situations"

See merge request !1215

Merge branch 'release-3.0' into 838-offline-fallback-page-for-django-legacy-pages-is-misleading-in-some-situations