It's possible for some extent, see the following answer:
https://tweaker.userecho.com/communities/1/topics/287-ability-to-run-application-or-even-better-trigger-a-media-button-on-clicking-on-empty-taskbar-space
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It's possible for some extent, see the following answer:
https://tweaker.userecho.com/communities/1/topics/287-ability-to-run-application-or-even-better-trigger-a-media-button-on-clicking-on-empty-taskbar-space