When you want to use a font in an application the font should be active. Typeface indicates activated/deactivated fonts by the dot next to each font name. Activated fonts have a blue dot, deactivated fonts have a grey dot.
To activate a font right click on the preview and choose “Activate”. This will mark the font active (blue indicator) and will add it to the ‘Activated’ tag.
You can also drag and drop fonts on the ‘Activated’ tag in the sidebar. To deactivate hold Option when dropping.
It is recommended to have not too many fonts activated at once, as it will degrade the performance of macOS. Make sure to deactivate some fonts you don’t use often.
Typeface will activate your fonts in-place. This means that Typeface won’t copy or move your font files, but will simply reference them. The advantage is that you can manage your files & directories however you want in Finder, Typeface won’t touch them.
System fonts & directories
There are three special font directories on macOS:
~/Library/Fonts/(user fonts, only visible to you)
/Library/Fonts(computer fonts, visible to all users of your Mac)
/System/Library/Fonts/(protected system fonts)
Fonts located in the system font directory are protected by Typeface and cannot be deactivated, because they’re required by macOS. You can deactivate the fonts in the user and computer fonts directories, but this is not recommended. These directories are monitored by macOS and their fonts will be automatically activated by the system if you add or change one of those files.
Fonts are referred to by their Post Script name. If multiple (active) fonts have the same name, the system does not know which font to choose. To prevent these conflicts, Typeface offers to deactivate other fonts with the same name first before you can activate the new fonts. Note that Typeface will protect System fonts, which means that you cannot activate fonts that create conflicts with System fonts.
With Auto Activation Typeface automatically makes fonts available to other apps when they request it. For example: You open a Pages document which uses the font ‘Frutiger’. Normally if this font is inactive (and therefore not usable) Pages will substitute this font for another one. When Auto Activation is enabled Typeface checks if you have imported ‘Frutiger’ to your library and automatically activates it for the Pages app so it can use it.
The benefit of auto activation is that you can keep many fonts inactive, which lowers system resource usage. And you don’t have to manually activate fonts when you open documents.
Not all apps properly request the font they want to use, so not all apps work. But most ‘native’ macOS apps should. You can turn this feature on in the Preferences of Typeface (app restart is required if you change this setting).