download: Add snap warning

Author: MarcoFalke

_includes/templates/download.html

@@ -222,6 +222,15 @@ <h2 style="text-align: center">{{page.verify_download}}</h2>
     </ol>
   </details>
 
+  {% if page.version > 3 %}
+  <details>
+    <summary><strong>{{page.snap_instructions}}</strong></summary>
+
+    <p>{{page.snap_warning}}</p>
+
+  </details>
+  {% endif %}
+
   <h2 style="text-align: center">{{page.build_reproduction}}</h2>
 
   <p>{{page.additional_steps}}</p>

_posts/en/pages/2017-01-01-download.md

@@ -5,7 +5,7 @@ type: pages
 layout: page
 lang: en
 share: false
-version: 3
+version: 4
 
 ## These strings need to be localized.  In the listing below, the
 ## comment above each entry contains the English text.  The key before the
@@ -60,6 +60,7 @@ verification_recommended: "Download verification is optional but highly recommen
 windows_instructions: "Windows verification instructions"
 macos_instructions: "MacOS verification instructions"
 linux_instructions: "Linux verification instructions"
+snap_instructions: "Snap package verification instructions"
 download_release: "Click the link in the list above to download the release for your platform and wait for the file to finish downloading."
 download_checksums: "Download the list of cryptographic checksums:"
 cd_to_downloads: "Open a terminal (command line prompt) and Change Directory (cd) to the folder you use for downloads.  For example:"
@@ -91,6 +92,12 @@ gpg_download_page: "install it now"
 gpg_download_other: "or see other installation"
 gpg_download_options: "options."
 
+snap_warning: >
+  While the Snap packages use the deterministically generated executables, the
+  Snap tool itself does not provide a streamlined way to reveal the contents of
+  a Snap package. Thus, the Bitcoin Core project does not have the information
+  necessary to help you verify the Bitcoin Core Snap packages.
+
 ensure_checksum_matches: >
   Ensure that the checksum produced by the command above matches one of
   the checksums listed in the checksums file you downloaded earlier.  We