diff --git a/src/autocomplete/CommandProvider.js b/src/autocomplete/CommandProvider.js
index 609a8fa9a1..b13680ece2 100644
--- a/src/autocomplete/CommandProvider.js
+++ b/src/autocomplete/CommandProvider.js
@@ -64,6 +64,7 @@ export default class CommandProvider extends AutocompleteProvider {
         return matches.map((result) => ({
             // If the command is the same as the one they entered, we don't want to discard their arguments
             completion: result.command === command[1] ? command[0] : (result.command + ' '),
+            type: "command",
             component: <TextualCompletion
                 title={result.command}
                 subtitle={result.args}
diff --git a/src/autocomplete/CommunityProvider.js b/src/autocomplete/CommunityProvider.js
index d164fab46a..ffce1e71cf 100644
--- a/src/autocomplete/CommunityProvider.js
+++ b/src/autocomplete/CommunityProvider.js
@@ -84,6 +84,7 @@ export default class CommunityProvider extends AutocompleteProvider {
             ]).map(({avatarUrl, groupId, name}) => ({
                 completion: groupId,
                 suffix: ' ',
+                type: "community",
                 href: makeGroupPermalink(groupId),
                 component: (
                     <PillCompletion initialComponent={
diff --git a/src/autocomplete/NotifProvider.js b/src/autocomplete/NotifProvider.js
index 432388c255..60a3352f9b 100644
--- a/src/autocomplete/NotifProvider.js
+++ b/src/autocomplete/NotifProvider.js
@@ -42,6 +42,7 @@ export default class NotifProvider extends AutocompleteProvider {
             return [{
                 completion: '@room',
                 completionId: '@room',
+                type: "at-room",
                 suffix: ' ',
                 component: (
                     <PillCompletion initialComponent={<RoomAvatar width={24} height={24} room={this.room} />} title="@room" description={_t("Notify the whole room")} />
diff --git a/src/autocomplete/RoomProvider.js b/src/autocomplete/RoomProvider.js
index f118a06b9e..b94edf590c 100644
--- a/src/autocomplete/RoomProvider.js
+++ b/src/autocomplete/RoomProvider.js
@@ -89,6 +89,7 @@ export default class RoomProvider extends AutocompleteProvider {
                 return {
                     completion: displayAlias,
                     completionId: displayAlias,
+                    type: "room",
                     suffix: ' ',
                     href: makeRoomPermalink(displayAlias),
                     component: (
diff --git a/src/autocomplete/UserProvider.js b/src/autocomplete/UserProvider.js
index d4a5ec5e74..62ae5d4970 100644
--- a/src/autocomplete/UserProvider.js
+++ b/src/autocomplete/UserProvider.js
@@ -114,6 +114,7 @@ export default class UserProvider extends AutocompleteProvider {
                     // relies on the length of the entity === length of the text in the decoration.
                     completion: user.rawDisplayName,
                     completionId: user.userId,
+                    type: "user",
                     suffix: (selection.beginning && range.start === 0) ? ': ' : ' ',
                     href: makeUserPermalink(user.userId),
                     component: (
diff --git a/src/editor/autocomplete.js b/src/editor/autocomplete.js
index beb155f297..3ee69dc477 100644
--- a/src/editor/autocomplete.js
+++ b/src/editor/autocomplete.js
@@ -100,19 +100,21 @@ export default class AutocompleteWrapperModel {
     _partForCompletion(completion) {
         const {completionId} = completion;
         const text = completion.completion;
-        const firstChr = completionId && completionId[0];
-        switch (firstChr) {
-            case "@": {
-                if (completionId === "@room") {
-                    return [this._partCreator.atRoomPill(completionId)];
-                } else {
-                    return this._partCreator.createMentionParts(this._partIndex, text, completionId);
-                }
-            }
-            case "#":
+        switch (completion.type) {
+            case "room":
                 return [this._partCreator.roomPill(completionId)];
-            // used for emoji and command completion replacement
+            case "at-room":
+                return [this._partCreator.atRoomPill(completionId)];
+            case "user":
+                // not using suffix here, because we also need to calculate
+                // the suffix when clicking a display name to insert a mention,
+                // which happens in createMentionParts
+                return this._partCreator.createMentionParts(this._partIndex, text, completionId);
+            case "command":
+                // command needs special handling for auto complete, but also renders as plain texts
+                return [this._partCreator.command(text)];
             default:
+                // used for emoji and other plain text completion replacement
                 return [this._partCreator.plain(text)];
         }
     }
diff --git a/src/editor/parts.js b/src/editor/parts.js
index 883eff8679..f0b713beb6 100644
--- a/src/editor/parts.js
+++ b/src/editor/parts.js
@@ -456,15 +456,20 @@ export class CommandPartCreator extends PartCreator {
     createPartForInput(text, partIndex) {
         // at beginning and starts with /? create
         if (partIndex === 0 && text[0] === "/") {
-            return new CommandPart("", this._autoCompleteCreator);
+            // text will be inserted by model, so pass empty string
+            return this.command("");
         } else {
             return super.createPartForInput(text, partIndex);
         }
     }
 
+    command(text) {
+        return new CommandPart(text, this._autoCompleteCreator);
+    }
+
     deserializePart(part) {
         if (part.type === "command") {
-            return new CommandPart(part.text, this._autoCompleteCreator);
+            return this.command(part.text);
         } else {
             return super.deserializePart(part);
         }