Manager for the font and complex text layout servers. [TextServerManager] is the API backend for loading, enumeration and switching [TextServer]s. Note: Switching text server at runtime is possible, but will invalidate all fonts and text buffers. Make sure to unload all controls, fonts, and themes before doing so. Finds an interface by its name. Returns the interface registered at a given index. Returns the number of interfaces currently registered. Returns text server supported features (binary OR). Returns the interface name registered at a given index. Returns a list of available interfaces the index and name of each interface. Returns the primary [TextServer] interface. Sets (and initializes it if required) interface registered at a given index as the primary. Invalidates all references to the fonts and text buffers.