Free FEM to be installed or online

    https://freefem.org/

    FEM software. Install is normally required (Mac, Windows, Linux) … but an online version is available (look at the right of the top menu).

    Works with a scripting console, so not very WYSIWYG, but you are always under the control of what is being calculated, and ready for iterations.

    Source code available, so as an active community for support

    Free, No registration, Download/Install required