Does ROS2 launch.xml support inline yaml like <rosparam>?

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In ROS1, you could inline your yaml file in the launch file with the <rosparam> tag as described here.

Example:

<rosparam>
  a: 1
  b: 2
</rosparam>

Is this format supported in ROS2?

From the migration guide, it seems <rosparam> is replaced with <param from> which only supports taking in a yaml file

Additionally, how do I do substitution akin to the following

<rosparam param="whitelist" subst_value="True">$(arg whitelist)</rosparam>

using the new ROS2 xml syntax?