[CONTENT-CHANGE] add: recommended Firefox extensions

[atomGit]

Firefox Extensions - My Picks

there's probably thousands of such lists floating around, however i think the value with this one is that a) i offer advice on how to choose a Firefox extension, particularly what to look out for, and b) many of the extensions listed are privacy and security related

not sure where this would fit best - perhaps 5_Privacy_Respecting_Software.md or the How-To Guides section

[Lissy93]

Thanks, this looks like a really resource, will properly go through it and test it out tomorrow -thanks for the suggestion 🙌