Jess mentions in her talk a few times that context-switching suits her working style and personality. Then she talks about the variety of types of tasks, where all have a common theme: helping quality emerge. She's in meetings with designers, developers, and support. She does exploratory testing and test automation. She works on requirements to discuss them, and the final checks. And as a lone tester, she might share her time in some way with several feature or product teams. Overall, she is responsible for defining where she will be, and not sticking to someone else's shallow notion of what a "tester" should do.
I loved the talk, perhaps because I too am a lone tester with a lot of freedom to put things together in whatever way I feel helps us. I tend to identify all sorts of things that don't seem to be getting done, making some of them visible and doing some of them myself. There's no task I wouldn't be allowed to do.
When Jess talks about context-switching, my brain right away decides she does not mean that, but she means small batches. Finishing one small thing before taking another small thing. Not interrupting in the middle and ending up trashing. But the natural state where you can do something and then it's done. There will be more like it, but they won't be the same.
Learn to love small batches. Releasing daily to production is the most liberating experience I have. Small changes are smaller risks and smaller to test. And while testing is never done, delivering things over warehousing investments without returns is rewarding on its own.
I feel that if you know how to create small batches - for you and for people around you - you'll do great as a lone tester.