As with T216399, project searches are direct - users can search for one project at a time (such as en.wikipedia.org). But users might want to search all Wikipedia projects (*.wikipedia.org). We should support this.
@Samwalton9 I would like to work on this but have a small doubt here. Can a user enter multiple * in the project field or will a user be allowed to enter any regex string? Also can a * be present anywhere in the string (such as en.wiki* .org) or will it be present only in the beginning as mentioned above?