diff --git a/data/web/corefork.telegram.org/api/stickers.html b/data/web/corefork.telegram.org/api/stickers.html
index 5bfab363f2..2fc9000124 100644
--- a/data/web/corefork.telegram.org/api/stickers.html
+++ b/data/web/corefork.telegram.org/api/stickers.html
@@ -74,8 +74,17 @@ document#8fd4c4d8 flags:# id:long…">
 <p>They're identified by <code>mime_type</code> field of the associated <a href="/constructor/document">document</a>, always equal to <code>image/webp</code>.</p>
 <p>See <a href="/stickers#static-stickers-and-emoji">here »</a> for tips on how to create the perfect static sticker, and <a href="#creating-stickersets">here »</a> for info on how to upload it using the API.</p>
 <h4><a class="anchor" href="#animated-stickers" id="animated-stickers" name="animated-stickers"><i class="anchor-icon"></i></a>Animated stickers</h4>
-<p>Animated stickers are vector 
-They're identified by <code>mime_type</code> field of the associated <a href="/constructor/document">document</a>, always equal to <code>application/x-tgsticker</code>.</p>
+<p>Animated stickers are <a href="https://en.wikipedia.org/wiki/Lottie_(file_format)">Lottie vector animations »</a>.  </p>
+<p>Telegram uses a special <code>.tgs</code> file format for lottie animations, which consists in a gzipped bodymovin JSON file, playable using the <a href="https://github.com/Samsung/rlottie">rlottie</a> library.  </p>
+<p>Lottie animation specs:</p>
+<ul>
+<li>The canvas size must be 512х512 pixels.</li>
+<li>Objects must not leave the canvas.</li>
+<li>Animation length must not exceed 3 seconds.</li>
+<li>All animations must be looped.</li>
+<li>All animations must run at 60 Frames Per Second.</li>
+</ul>
+<p>They're identified by <code>mime_type</code> field of the associated <a href="/constructor/document">document</a>, always equal to <code>application/x-tgsticker</code>.</p>
 <p>See <a href="/stickers#creating-animations">here »</a> for tips on how to create the perfect animated sticker, and <a href="#creating-stickersets">here »</a> for info on how to upload it using the API.</p>
 <h4><a class="anchor" href="#video-stickers" id="video-stickers" name="video-stickers"><i class="anchor-icon"></i></a>Video stickers</h4>
 <p>Video stickers are <a href="https://en.wikipedia.org/wiki/VP9">VP9</a> videos with the following specs:</p>
@@ -101,7 +110,6 @@ They're identified by <code>mime_type</code> field of the associated <a href="/c
 ---functions---
 
 <a href='/method/messages.getMaskStickers'>messages.getMaskStickers</a>#640f82b8 hash:<a href='/type/long'>long</a> = <a href='/type/messages.AllStickers'>messages.AllStickers</a>;
-
 <a href='/method/messages.getAttachedStickers'>messages.getAttachedStickers</a>#cc5b67cc media:<a href='/type/InputStickeredMedia'>InputStickeredMedia</a> = <a href='/type/Vector%20t'>Vector</a>&lt;<a href='/type/StickerSetCovered'>StickerSetCovered</a>&gt;;</code></pre>
 <h3><a class="anchor" href="#stickersets" id="stickersets" name="stickersets"><i class="anchor-icon"></i></a>Stickersets</h3>
 <pre><code><a href='/constructor/inputStickerSetID'>inputStickerSetID</a>#9de7a269 id:<a href='/type/long'>long</a> access_hash:<a href='/type/long'>long</a> = <a href='/type/InputStickerSet'>InputStickerSet</a>;