Put in a hack to allow images to go wider than 256 columns. If we see the x...

Put in a hack to allow images to go wider than 256 columns. If we see the x value go to 0 right after it's 255 and the image code and row number stay the same, treat it as a continuation. Issue 6335.

sources/iTermTextDrawingHelper.m

@@ -1739,7 +1739,7 @@ static BOOL iTermTextDrawingHelperIsCharacterDrawable(screen_char_t *c,
     if (![previousImageAttributes[iTermImageLineAttribute] isEqual:imageAttributes[iTermImageLineAttribute]]) {
         return NO;
     }
-    if ([previousImageAttributes[iTermImageColumnAttribute] integerValue] + 1 != [imageAttributes[iTermImageColumnAttribute] integerValue]) {
+    if ((([previousImageAttributes[iTermImageColumnAttribute] integerValue] + 1) & 0xff) != ([imageAttributes[iTermImageColumnAttribute] integerValue] & 0xff)) {
         return NO;
     }