Made this (GPT-4 made this actually) for myself mainly to do quick lookups on selected text. Add your api key and then your own system prompts in options. Then from context menu send selected text to ChatGPT with one of your prompts. Result should appear on top of page.I haven't looked much into publishing this on store yet, might do that later. At the moment, you have to load this in Developer mode via Load Unpacked button on extensions page in chrome.
Tip: if you have only one prompt enabled, context menu will not be nested.