File Magic is a reliable file viewer that makes easy the process of viewing, and working with a large range of file formats, including the often confusing and multifaceted "dot" extensions.
In case you encounter common formats such as .pdf, and even less common formats including . https://www.filemagic.com/en/page-layout-files/dot-file-extension/1-solution-for-all-your-dot-file-issues/