Properly escape strings for snippets

Surfaced when completing the `word_separators` setting.

Author: FichteFoll

plugins_/settings/known_settings.py

@@ -408,7 +408,9 @@ def _key_snippet(key, value, bol="", eol=",\n"):
             string: the contents field to insert into completions entry
         """
         encoded = sublime.encode_value(value)
-        encoded = encoded.replace("$", "\\$")  # escape snippet markers
+        encoded = encoded.replace("\\", "\\\\")  # escape snippet markers
+        encoded = encoded.replace("$", "\\$")
+        encoded = encoded.replace("}", "\\}")
 
         if isinstance(value, str):
             # create the snippet for json strings and exclude quotation marks