fix links sticking to mentionsline

src/components/mentions_line/mentions_line.scss

@@ -4,7 +4,7 @@
     color: var(--link);
   }
 
-  .mention-link:not(:last-child) {
+  .mention-link {
     margin-right: 0.25em;
   }
 }

src/components/rich_content/rich_content.jsx

@@ -121,6 +121,13 @@ export default Vue.component('RichContent', {
           // in MentionsLine
           return currentMentions !== null ? item.trim() : item
         }
+        // We add space with mentionsLine, otherwise non-text elements will
+        // stick to them.
+        if (currentMentions !== null) {
+          // single whitespace trim
+          item = item[0].match(/\s/) ? item.slice(1) : item
+        }
+
         currentMentions = null
         if (item.includes(':')) {
           item = ['', processTextForEmoji(

test/unit/specs/components/rich_content.spec.js

@@ -59,7 +59,7 @@ describe('RichContent', () => {
   it('replaces mention with mentionsline', () => {
     const html = p(
       makeMention('John'),
-      ' how are you doing today?'
+      '  how are you doing today?' // also testing single-trimming function
     )
     const wrapper = shallowMount(RichContent, {
       localVue,
@@ -74,7 +74,7 @@ describe('RichContent', () => {
 
     expect(wrapper.html()).to.eql(compwrap(p(
       mentionsLine(1),
-      ' how are you doing today?'
+      ' how are you doing today?' // space removed to compensate for <ML> padding
     )))
   })