How to add the hex token:
Use the extension’s background page (preferred)
Go to chrome://extensions/.
Enable Developer mode (toggle top right).
Find your readitlater extension.
Click “service worker” link under “Inspect views”. This opens a DevTools console for the extension background.

Now paste:
chrome.storage.sync.set({ READITLATER_TOKEN: "2cb9f5b875af65b4de7ff7736e384ae9d33e1bf2176c45afac24a713804ef6d4" });