fix warnings about contains an unrecognized relative link

Author: unixfox

docs/faq.md

@@ -138,7 +138,7 @@ sent by your browser.
 **A:** This problem can occur in different scenarios:
 
 * If you are the one that have installed Invidious, please read the page
-  ["All the YouTube error messages explained with solutions"](/youtube-errors-explained/)
+  ["All the YouTube error messages explained with solutions"](./youtube-errors-explained.md)
 
 * If you're trying to watch a music clip, Youtube is likely blocking the
   video stream. Try enabling `Proxy videos` in the preferences (or add

docs/register-user.md

@@ -1,6 +1,6 @@
 # Registering users manually
 
-You might want to disable registration in your [instance config](/configuration), but still have a quick way to manually register users upon request. To do so, first set up a separate instance that only listens on localhost, has registration enabled,
+You might want to disable registration in your [instance config](./configuration.md), but still have a quick way to manually register users upon request. To do so, first set up a separate instance that only listens on localhost, has registration enabled,
 and captchas as well as background jobs disabled. Make sure you have a way to start it easily with just one or a few commands, e.g. via a systemd service. Then, use something like the script below (in the example, the instance is started via a systemd
 service called `podman-invidious_register`, and it listens on localhost port 21742. **Warning**: This script is vulnerable to SQL injections. Only use trusted inputs; if you want to make a custom signup form and use this as a backend, be sure to
 sanitize inputs.

docs/youtube-errors-explained.md

@@ -44,7 +44,7 @@ First make sure that you are running the latest version of Invidious and you are
 After which you can try these solutions:
 
 - Change your public IP address. Reboot your router or by configuring a proxy in Invidious: https://github.com/iv-org/invidious/blob/2150264d849771df8f15bab172ab6d87eeb80c55/config/config.example.yml#L176-L185
-- If you have IPv6 on the computer hosting Invidious, you can try to rotate your IPv6 public address, tutorial available here: "[Rotate your IPv6 address for escaping YouTube blocking](/ipv6-rotator/)"
+- If you have IPv6 on the computer hosting Invidious, you can try to rotate your IPv6 public address, tutorial available here: "[Rotate your IPv6 address for escaping YouTube blocking](./ipv6-rotator.md)"
 
 All of these options do not guarantee you to bring back Invidious to working conditions. These are just advices for trying to unblock your Invidious instance from YouTube. Make sure to always specify any modification being done to your Invidious when reporting issues.