When we detect version mismatch always retry getting features.

JitsiConference.js

         id,
         participant);
 
-    this._updateFeatures(participant)
-        .catch(() =>
-
-            // there was probably a mismatch, lets try one more time and give up
-            this._updateFeatures(participant)
-                .catch(error => {
-                    logger.warn(`Failed to discover features of ${jid}`, error);
-                }));
+    this._updateFeatures(participant);
 
     this._maybeStartOrStopP2P();
     this._maybeSetSITimeout();
 /**
  * Updates features for a participant.
  * @param {JitsiParticipant} participant - The participant to query for features.
- * @returns {Promise<Set<String> | never>}
+ * @returns {void}
  * @private
  */
 JitsiConference.prototype._updateFeatures = function(participant) {
-    return this.xmpp.caps.getFeatures(participant.getJid())
+    participant.getFeatures()
         .then(features => {
             participant._supportsDTMF = features.has('urn:xmpp:jingle:dtmf:0');
             this.updateDTMFSupport();
             if (features.has('http://jitsi.org/protocol/jigasi')) {
                 participant.setProperty('features_jigasi', true);
             }
-        });
+        })
+        .catch(() => false);
 };
 
 /**

JitsiParticipant.js

 
 import { Strophe } from 'strophe.js';
 
+import { getLogger } from 'jitsi-meet-logger';
+
 import * as JitsiConferenceEvents from './JitsiConferenceEvents';
 import { ParticipantConnectionStatus }
     from './modules/connectivity/ParticipantConnectionStatus';
 import * as MediaType from './service/RTC/MediaType';
 
+const logger = getLogger(__filename);
+
 /**
  * Represents a participant in (i.e. a member of) a conference.
  */
      * @returns {Promise<Set<String>, Error>}
      */
     getFeatures(timeout = 5000) {
-        return this._conference.xmpp.caps.getFeatures(this._jid, timeout);
+        return this._conference.xmpp.caps.getFeatures(this._jid, timeout)
+            .catch(error => {
+                // when we detect version mismatch we return a string as error
+                // we want to retry in such case
+                if (error && error.constructor === String) {
+                    return this._conference.xmpp.caps.getFeatures(this._jid, timeout);
+                }
+
+                logger.warn(`Failed to discover features of ${this._jid}`, error);
+
+                return Promise.reject(error);
+            });
     }
 
     /**