You can delete a Mergin project either on your PC (locally) or on the Mergin server. To be able to delete the project on the Mergin server, you need to first delete the files locally.
To delete a project, in the Browser panel, right-click on the project and select Remove locally. This will remove the project from your PC, but the project will be still available on the Mergin server. You will be able to download the project again.
To delete a Mergin project on the server, it must not be available on the local PC (the project has “cloud” icon next to it). In such case, right-clicking on the project name will offer Remove from server option - using this option will remove the Mergin project completely. WARNING: this operation is not undoable and the project data are permanently deleted.