Consider donating all or most of your Mana on Manifold to charity before May 1.

Manifold is making multiple changes to the way Manifold works. You can read their announcement here. The main reason for donating now is that Mana will be devalued from the current 1 USD:100 Mana to 1 USD:1000 Mana on May 1. Thankfully, the 10k USD/month charity cap will not be in place until then.

Also this part might be relevant for people with large positions they want to sell now:

One week may not be enough time for users with larger portfolios to liquidate and donate. We want to work individually with anyone who feels like they are stuck in this situation and honor their expected returns and agree on an amount they can donate at the original 100:1 rate past the one week deadline once the relevant markets have resolved.

Since this is tagged "Existential risk": What does this have to do with existential risk? Or is it not supposed to be about existential risk, not even indirectly? As far as I can tell, the article does not talk about existential risk. I could make my own guesses and association of this topic with existential risk, but I would prefer if this is spelled out.

Here is another argument against Geometric utility: It does not work if negative utilities are involved: $u^p$ is undefined if $u$ is negative. And I think some real-world experiences that involve suffering have negative utility.

FHI has shut down yesterday: https://www.futureofhumanityinstitute.org/

Charging your phone is a very small amount of energy. The CO2-Emissions from that are less than what humans breathe out during an hour.

(some math with example values found through quick google searches, actual values depend on lot of factors and differ from source to source: 20 Wh to charge a phone, 1kg/kWh CO2 for energy, 0.66kg/day CO2 per human breathing. So a phone charge is 20g of CO2, which is equivalent to 20 * 24 / 660 = 0.73 hours of human breathing)

A relevant (imo) piece of information not in this post: The EA forum post that you are talking about was down-voted a lot. (I have down-voted too, although I don't remember why I did so at the time.)

This makes me less worried than I otherwise would have been.

edit: I did not see Jason's comment prior to posting mine, sorry for duplicate information.

I think this requires more elaboration how exactly the suggested system is supposed to work.

You are right, the page does contain the phrase "Give 10% of your income each year".(Somehow google has not picked it up so I did not find it). I think GWWC has made a mistake here. The text of the actual pledge does not have this constraint.

Maybe @graceadams or someone else from GWWC can clarify things and fix the formulation on their website?

Why are you under the impression that you have to give each year? I tried to google your quoted string but could not find an exact match.

As I interpret the GWWC pledge formulation, there is no condition when you have to donate, just how much.

eg people do care about climate change, nuclear war, rogue AI, deadly pandemics

But those things are also important without longtermism. So you can make non-longtermist PR for things that longtermists like, but it would feel dishonest if you hide the part with large numbers of people millions of years into the future.