Picture: images with & in URL are broken

[dos1]

When a Picture tries to download an image sent as a plain link in a chat message, it gets a garbled URL that has its & characters replaced with &, leading to download failure and broken_image_filled being displayed instead of the linked image.

I haven't looked deep enough to know whether this fix is reasonable, but it does make things work:

diff --git a/app/widgets/Picture/Picture.php b/app/widgets/Picture/Picture.php
index 71047419c..512046389 100644
--- a/app/widgets/Picture/Picture.php
+++ b/app/widgets/Picture/Picture.php
@@ -10,7 +10,7 @@ class Picture extends Base
 
     public function display()
     {
-        $url = urldecode($this->get('url'));
+        $url = html_entity_decode(urldecode($this->get('url')));
         $parsedUrl = parse_url($url);
         if (
             is_array($parsedUrl)
@@ -27,7 +27,7 @@ class Picture extends Base
         $max = $headers["download_content_length"] > $this->compressLimit ? $this->compressLimit : $headers["download_content_length"];
 
         $ch = curl_init();
-        curl_setopt($ch, CURLOPT_URL, $this->get('url'));
+        curl_setopt($ch, CURLOPT_URL, $url);
         curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
         curl_setopt($ch, CURLOPT_HEADER, true);
         curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);