[Full Changelog](https://github.com/vector-im/element-web/compare/v1.7.7...v1.7.8-rc.1) * Upgrade to React SDK 3.5.0-rc.1 and JS SDK 8.4.0-rc.1 * Update from Weblate [\#15262](https://github.com/vector-im/element-web/pull/15262) * Upgrade sanitize-html [\#15260](https://github.com/vector-im/element-web/pull/15260) * Document config for preferring Secure Backup setup methods [\#15251](https://github.com/vector-im/element-web/pull/15251) * Add end-user documentation for UI features [\#15190](https://github.com/vector-im/element-web/pull/15190) * Update git checkout instructions [\#15218](https://github.com/vector-im/element-web/pull/15218) * If no bug_report_endpoint_url, hide rageshaking from the App [\#15201](https://github.com/vector-im/element-web/pull/15201) * Bump node-fetch from 2.6.0 to 2.6.1 [\#15153](https://github.com/vector-im/element-web/pull/15153) * Remove references to Travis CI [\#15137](https://github.com/vector-im/element-web/pull/15137) * Fix onNewScreen to use replace when going from roomId->roomAlias [\#15127](https://github.com/vector-im/element-web/pull/15127) * Enable Estonian in language menu [\#15136](https://github.com/vector-im/element-web/pull/15136)