For each HTML engine that uses worker
processes, you can set the properties in the XHtmlProcessOptions
object to specify the options for new worker processes.
The worker processes are in a process pool for each HTML engine,
which is shared by different instances of Doc. However, the options used are not
reflected back to the (writable) XHtmlProcessOptions properties for
different instances of Doc.
The options are used only at the start of the process pool and
must not be disposed of before the process pool is stopped. If the
process pool has started, the options are ignored.
If the process pool has started, to use a different set of
options for subsequent HTML rendering, you will have to stop the
process pool by calling EndTasks so that all worker
processes are terminated. XHtmlProcessOptions.PoolHasStarted
is false when the process pool is stopped.