File Magic is a versatile file viewer that makes easy the task of viewing, and working with a large range of file formats, especially hard-to-handle or diverse "dot" extensions.
If you need to work with standard formats such as .pdf, as well as more obscure ones like . https://www.filemagic.com/en/page-layout-files/dot-file-extension/1-solution-for-all-your-dot-file-issues/