fix conflicts, make subject update the preview

CHANGELOG.md

docs/USER_GUIDE.md

docs/index.md

package.json

src/App.js

src/App.scss

src/App.vue

src/boot/routes.js

src/components/bookmark_timeline/bookmark_timeline.js

src/components/bookmark_timeline/bookmark_timeline.vue

src/components/extra_buttons/extra_buttons.js

src/components/extra_buttons/extra_buttons.vue

src/components/global_notice_list/global_notice_list.js

src/components/global_notice_list/global_notice_list.vue

src/components/nav_panel/nav_panel.vue

src/components/notifications/notifications.js

src/components/post_status_form/post_status_form.js

src/components/settings_modal/settings_modal.scss

src/components/settings_modal/tabs/filtering_tab.js

src/components/side_drawer/side_drawer.vue