TeXShop 2.26 came with new macros. If you upgraded from a previous version, you will not automatically see those new items. If you never edited the default macro set, you can obtain the new macros by going to the folder ~/Library/TeXShop and removing the entire Macros folder inside. The next time TeXShop starts, it will recreate this folder with the latest macros. It is not enough to remove the contents of the Macros folder; the entire folder must be removed.

If you have edited the default macros and want to add the new macro set, remove the Macros folder temporarily and let TeXShop create a new macro set. Then add your old macros using the Macro Editor.

TeXShop 2.26 came with new engine files in the "Inactive" folder. If you upgraded from a previous version, you will not automatically see them. You can obtain the new engines by going to the folder ~/Library/TeXShop and moving the entire Engines folder to the Desktop. The next time TeXShop starts, it will recreate this folder. You can then move old engine files you may have created yourself from the copy on the desktop into the new Engines folder.

TeXShop 1.35 came with new templates by Will Robertson. If you upgraded from a previous version, you will not see these templates. You can obtain them by going to the folder ~/Library/TeXShop and moving the entire Templates folder to the Desktop. The next time TeXShop starts, it will recreate this folder with the latest Templates. You can then move old Templates you have edited from the folder on the desktop to the newly created folder ~/Library/TeXShop/Templates.

How do I configure TeXShop?
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