Fix link syntax

README.md

@@ -32,7 +32,7 @@ You are welcome to use the offline desktop version. However, I highly recommend
 hosted web version. To the best of my knowledge, no one is using this, and I'm planning
 on taking it down soon. If you need to export your data, log in as normal and then go to
 [https://api.thinktool.io/state](https://api.thinktool.io/state). Alternatively,
-write to me at [mailto:jonas@thinktool.io](jonas@thinktool.io), and I'll do it for you.
+write to me at [jonas@thinktool.io](mailto:jonas@thinktool.io), and I'll do it for you.
 This is just a JSON export – it's up to you to turn it into something useful.
 
 ## Comparison to other software