Effective altruism movement building seems potentially very high impact. I remember once seeing estimates that each dollar spent in it raised many dollars of EA donations. Does anyone know of good places to donate for movement growth and or estiamtes of its effectiveness?

Here is the post presenting GWWC's impact evaluation (I also looked into it), and here is a post from Melanie Basnak reflecting on Open Philanthropy's (OP's) grantmaking on effective giving.
Thanks!