Chrome extension for slack that allows you to mash one key on the home row over and over again (d, for 'do it') to read all of your messages.
https://www.mattcutts.com/blog/how-to-install-a-chrome-extension-from-github/
If you are into this sort of thing, https://refined.chat/ is perhaps the most full-featured slack browser extension.
hot-reload.js is from https://stackoverflow.com/a/40454227/6090676, and is just for development purposes.