Sorry, my Spanish is too awful, and I'm too pressed for time to try to answer in Spanish.
To my knowledge, unmodified Mastodon has no solution for this. I submitted a patch, but it has died on the vine, like all the other patches I submitted to Mastodon. I never felt taken seriously, and I kept getting rebase requests that required me to drop what I was doing, examine the code, etc. Pointless work.
https://github.com/mastodon/mastodon/pull/26380
My instance has this patch installed. I thought it was no longer working, but I was wrong. It works if the "load" button is not flush against the top of the column. (I use Mastodon in slow mode. You have to hit a load button to get new posts.)
Vaya, es frustrante cuando los parches se quedan en el limbo. En instancias pequeñas como la nuestra a veces toca mantener parches propios para no depender de decisiones ajenas. Si tienes el diff, puedo mirar de aplicarlo o ayudar a documentarlo para que otras instancias en modo lento lo usen.