Hide default encryption algorithm

When the default encryption algorithm is used, we hide it to remove some jargon
from the app. For any other algorithm, we continue showing it and add
"unrecognised".

Fixes element-hq/element-web#8829

src/TextForEvent.js

@@ -444,10 +444,19 @@ function textForHistoryVisibilityEvent(event) {
 
 function textForEncryptionEvent(event) {
     const senderName = event.sender ? event.sender.name : event.getSender();
-    return _t('%(senderName)s turned on end-to-end encryption (algorithm %(algorithm)s).', {
-        senderName,
-        algorithm: event.getContent().algorithm,
-    });
+    if (event.getContent().algorithm === "m.megolm.v1.aes-sha2") {
+        return _t('%(senderName)s turned on end-to-end encryption.', {
+            senderName,
+        });
+    }
+    return _t(
+        '%(senderName)s turned on end-to-end encryption ' +
+        '(unrecognised algorithm %(algorithm)s).',
+        {
+            senderName,
+            algorithm: event.getContent().algorithm,
+        },
+    );
 }
 
 // Currently will only display a change if a user's power level is changed

src/i18n/strings/en_EN.json

@@ -256,7 +256,8 @@
     "%(senderName)s made future room history visible to all room members.": "%(senderName)s made future room history visible to all room members.",
     "%(senderName)s made future room history visible to anyone.": "%(senderName)s made future room history visible to anyone.",
     "%(senderName)s made future room history visible to unknown (%(visibility)s).": "%(senderName)s made future room history visible to unknown (%(visibility)s).",
-    "%(senderName)s turned on end-to-end encryption (algorithm %(algorithm)s).": "%(senderName)s turned on end-to-end encryption (algorithm %(algorithm)s).",
+    "%(senderName)s turned on end-to-end encryption.": "%(senderName)s turned on end-to-end encryption.",
+    "%(senderName)s turned on end-to-end encryption (unrecognised algorithm %(algorithm)s).": "%(senderName)s turned on end-to-end encryption (unrecognised algorithm %(algorithm)s).",
     "%(userId)s from %(fromPowerLevel)s to %(toPowerLevel)s": "%(userId)s from %(fromPowerLevel)s to %(toPowerLevel)s",
     "%(senderName)s changed the power level of %(powerLevelDiffText)s.": "%(senderName)s changed the power level of %(powerLevelDiffText)s.",
     "%(senderName)s changed the pinned messages for the room.": "%(senderName)s changed the pinned messages for the room.",