Just so you know this has been reported and is a known issue (happens to me on the browser as well). Presumably, it is due to Lemmyβs use of websockets for API requests, which has its issues for this particular application.
This has been addressed in version 0.18.0 as, among quite a few other changes, an HTTP API is now in place for API requests which will (should) resolve this issue.
Lemmy.world is currently on back end version 0.17.4 which still uses websockets. You can see this at the bottom of every page. The reason for this is that version 18 removed the ability to use Captcha for account registration. Given the size of the instance and its rapidly growing user base, and the fact that we are still accepting registrations, we simply must have the ability to leverage Captchas to mitigate the bot spam signups, which has been an issue.
We have tested the 0.18.1rc build (non-official release) in order to try and get this new functionality as soon as possible, but as you can see in the post 18.1 needs some time to bake still - at least for large instances.
This is definitely being discussed among the admin/mod team and we will be upgrading as soon as we realistically can while providing a stable - usable - experience.