Added reply template documentation

FAQ.md

@@ -333,6 +333,7 @@ Fonts, sizes, colors, etc should be material design whenever possible.
 * [(176) When will a message be considered safely transported?](#user-content-faq176)
 * [(177) What does 'Sensitivity' mean?](#user-content-faq177)
 * [(178) Why are widgets not updating?](#user-content-faq178)
+* [(179) What are reply templates?](#user-content-faq179)
 
 [I have another question.](#user-content-get-support)
 
@@ -4608,6 +4609,24 @@ Please see [this video](https://www.youtube.com/watch?v=ywQrYJ6rtnM) about how t
 
 <br />
 
+<a name="faq179"></a>
+**(179) What are reply templates?**
+
+Reply templates are predefined answer texts.
+
+You can reply with a template, insert a template via the three-dots overflow menu in the message editor,
+and long press on an open space to insert a snippet (the latter requires Android 6 Marshmallow or later).
+
+Templates can have the following options:
+
+* *Default*: template to use when writing a new message
+* *Use as read receipt*: template to use instead of the default read receipt text
+* *Favorite*: template will be added in the main reply popup menu
+* *Snippet*: template will be used as text fragment (since version 1.1857)
+* *Hide from menus*: template will be hidden (disabled)
+
+<br />
+
 <h2><a name="get-support"></a>Get support</h2>
 
 &#x1F30E; [Google Translate](https://translate.google.com/translate?sl=en&u=https://github.com/M66B/FairEmail/blob/master/FAQ.md%23user-content-get-support)