I could spend hours on Google Maps researching areas near and far, looking up restaurants and attractions and reading reviews and menus.
Fantasy house hunting on Right move
Fantasy holiday shopping on Booking.com
Going down a weird Wikipedia rabbit hole
Catching up on the news
Reading film review on IMDB
Delete old files and photos on my phone to free up memory
Mumsnet binge
I like some of the Guardian articles that have interesting reader comments
Do an online course
Learn a language
Colouring book while listening to an audio book
Organise my life- lists, budgets, shopping, dealing with appointments & my calender
Lurk in the kitchen and chat to anyone who's happy to chat.
Read a book- I love the suggestions pp have said to put it as a pdf on screen
I could easily fill 7 empty hours haha