The `runtime` module provides access to information about Firefox's runtime environment. All properties exposed are read-only. For more information, see [nsIXULRuntime][nsIXULRuntime]. [nsIXULRuntime]: https://developer.mozilla.org/en/XPCOM_Interface_Reference/nsIXULRuntime @property {boolean} This value is `true` if Firefox was started in safe mode, otherwise `false`. @property {string} A string identifying the current operating system. For example, . `"WINNT"`, `"Darwin"`, or `"Linux"`. See [OS_TARGET][OS_TARGET] for a more complete list of possible values. [OS_TARGET]: https://developer.mozilla.org/en/OS_TARGET @property {long} The type of the caller's process, which will be one of these constants\:

Constant	Value	Description
PROCESS_TYPE_DEFAULT	0	The default (chrome) process.
PROCESS_TYPE_PLUGIN	1	A plugin subprocess.
PROCESS_TYPE_CONTENT	2	A content subprocess.
PROCESS_TYPE_IPDLUNITTEST	3	An IPDL unit testing subprocess.

@property {string} A string identifying the target widget toolkit in use. @property {string} A string identifying the [ABI][ABI] of the current processor and compiler vtable. This string takes the form \<`processor`\>-\<`compilerABI`\>, for example\: "`x86-msvc`" or "`ppc-gcc3`". [ABI]: https://developer.mozilla.org/en/XPCOM_ABI