Instruct users to add code/errors as text in issues

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -45,7 +45,8 @@ body:
     label: Issue description
     description: |
       Describe your issue briefly. What doesn't work, and how do you expect it to work instead?
-      You can include images or videos with drag and drop, and format code blocks or logs with <code>```</code> tags.
+      You can include images or videos with drag and drop, and format code blocks or logs with <code>```</code> tags, on separate lines before and after the text. (Use <code>```gdscript</code> to add GDScript syntax highlighting.)
+      Please do not add code examples or error messages as screenshots, but as text, this helps searching for issues and testing the code. If you are reporting a bug in the editor interface, like the script editor, please provide both a screenshot *and* the text of the code to help with testing.
   validations:
     required: true