dense igloo
When I changed the settings for the long-press word selection, I deactivated the default dictionary option and enabled the translator pop-up.
This worked initially, but then the word remained highlighted, and touching the screen anywhere would cause the translator to reappear.
I tried using the pop-up chooser, and that seemed to resolve the issue. I'm not sure if it's relevant, but I was using an EPUB file.
I performed a hard restart by pressing the on/off button for 10 seconds, and now the feature is working correctly.
ornate pewter