diff --git a/slides/k8s/prometheus.md b/slides/k8s/prometheus.md
index 9032657c..049bea18 100644
--- a/slides/k8s/prometheus.md
+++ b/slides/k8s/prometheus.md
@@ -60,10 +60,12 @@
 
   (by default: every minute; can be more/less frequent)
 
-- If you're worried about parsing overhead: exporters can also use protobuf
-
 - The list of URLs to scrape (the *scrape targets*) is defined in configuration
 
+.footnote[Worried about the overhead of parsing a text format?
+<br/>
+Check this [comparison](https://github.com/RichiH/OpenMetrics/blob/master/markdown/protobuf_vs_text.md) of the text format with the (now deprecated) protobuf format!]
+
 ---
 
 ## Defining scrape targets