Update 1.0.md

Added the string-length again, and a small mention that all shows in the index already have a GUID assigned. Also fixed line breaks around the QR code.

docs/1.0.md

@@ -481,6 +481,8 @@ changes. This means that when a podcast moves from one hosting platform to anoth
 
 Using this pattern, podcasts can maintain a consistent identity across the open RSS ecosystem without a central authority.
 
+**Tips:** A GUID is 36 characters long. All podcasts in the Podcast Index have already been assigned a GUID; but if one exists in the RSS feed, that value is canonical.
+
 #### Parent
 `<channel>`
 
@@ -514,6 +516,7 @@ The format of the link is `https://(a podcast website link)#fastfollow-(type):(a
 `type` is currently `podcast`, but may be extended in future.
 
 A working example is https://podnews.net/podcast/i8xe9/listen#fastfollow-podcast:9b024349-ccf0-5f69-a609-6b82873eab3c or the QR code given below.
+
 ![podnews-qr](https://user-images.githubusercontent.com/231941/127796108-d819de43-6c0e-4c7b-9579-ed1f19989443.png)
 
 When scanned on a mobile phone's camera app, this link will go to the specified podcast website. Behavior of this website is up to the creator: some may use a default homepage, others may sniff the useragent and open a default podcast app on a device. In the working example, above, an iPhone user may be taken to Apple Podcasts; an Android user may be taken to Google Podcasts; and another device will be given a page with a player.