My hosting provider does not allow to perform cronjobs more often than once at two hours. Therefore, NC 20.0.8 > Settings > Background Tasks alerts each time, when cron has not been performed within the last five minutes.
I use my NC installation almost exclusively for my own private purposes. So, there are only less activities on it.
Can I, without running into problems, alter the settings of NC in order to mute the warning as long as the cronjobs has been performed at least everty two hours?
To be honest, I would consider changing the provider. It’s not like that there is anything exclusive about offering webhosting these days, except that certain providers are exclusively bad at it. If a provider does not suit your needs, find one that does.
If for some reason changing the hoster is not possible, you could consider the Webcron method, but it requires an external service like https://www.easycron.com/. Or in the worst case, you can switch to AJAX.
If a provider does not suit your needs, find one that does.