MacOS: How to change the default app for a file<article>
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<p>Back in the pre-Mac OS X and macOS days, Apple’s System 9 and earlier relied on hidden metadata to associate files with apps. File extensions, those bits of text that follow a period at the end of a file (like .doc, .html, or .jpg) were optional, although often used for compatibility with other platforms and with web. On the web, file extensions are effectively mandatory so a browser knows how to handle a file appropriately.</p><p>Macworld reader Rick would like to monkey with that. He has a number of HTML templates, but to differentiate them from his production .html files, he puts the suffix .tt on them instead. Browsers don’t recognize these files by default. There’s a way to force an association between a file type and an application, but that application still has to recognize the extension.</p><p class="jumpTag"><a href="/article/3286190/os-x/change-default-app-macos.html#jump">To read this article in full, please click here[/url]</p></section></article>
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MacOS: How to change the default app for a file