Avoid intermediate objects while parsing TextTiles' bodies.

src/domain/session/room/timeline/tiles/BaseTextTile.js

@@ -28,22 +28,27 @@ export class BaseTextTile extends BaseMessageTile {
         return "message";
     }
 
-    _parseBody(body) {
+    _parseBody(body, _) {
         return stringAsBody(body.string);
     }
 
+    _getBodyFormat() {
+        return "plain";
+    }
+
     get body() {
         const body = this._getBody();
+        const format = this._getBodyFormat();
         // body.string is a string, so we can check for difference by just
         // doing an equality check
         // Even if the body hasn't changed, but the format has, we need
         // to re-fill our cache.
-        if (!this._messageBody || this._messageBody.sourceString !== body.string || this._messageFormat !== body.format) {
+        if (!this._messageBody || this._messageBody.sourceString !== body || this._messageFormat !== format) {
             // body with markup is an array of parts,
             // so we should not recreate it for the same body string,
             // or else the equality check in the binding will always fail.
             // So cache it here.
-            this._messageBody = this._parseBody(body);
+            this._messageBody = this._parseBody(body, format);
             this._messageFormat = body.format;
         }
         return this._messageBody;

src/domain/session/room/timeline/tiles/TextTile.js

@@ -19,7 +19,7 @@ import {parsePlainBody} from "../MessageBody.js";
 import {parseHTMLBody} from "../deserialize.js";
 
 export class TextTile extends BaseTextTile {
-    _getContentString(key, format, fallback = null) {
+    _getContentString(key, fallback = null) {
         const content = this._getContent();
         let val = content?.[key] || fallback;
         if (!val && val !== "") { // empty string is falsy, but OK here.
@@ -28,27 +28,30 @@ export class TextTile extends BaseTextTile {
         if (content.msgtype === "m.emote") {
             val = `* ${this.displayName} ${body}`;
         }
-        return { string: val, format };
+        return val;
     }
 
     _getPlainBody() {
-        return this._getContentString("body", "plain", "");
+        return this._getContentString("body", "");
     }
 
     _getFormattedBody() {
-        return this._getContentString("formatted_body", "html");
+        return this._getContentString("formatted_body");
     }
 
     _getBody() {
         return this._getFormattedBody() || this._getPlainBody();
     }
 
-    _parseBody(body) {
-        const string = body.string;
-        if (body.format === "html") {
-            return parseHTMLBody({ mediaRepository: this._mediaRepository, platform: this.platform }, string);
+    _getBodyFormat() {
+        return this._getContent()?.["formatted_body"] ? "html" : "plain"
+    }
+
+    _parseBody(body, format) {
+        if (format === "html") {
+            return parseHTMLBody({ mediaRepository: this._mediaRepository, platform: this.platform }, body);
         } else {
-            return parsePlainBody(string);
+            return parsePlainBody(body);
         }
     }
 }