FoxyImage is a tiny multi-process extension that adds a number of Image related actions to the Context Menu. Let me know if you want other functions added. Note: None of my extensions contain any tracking, advertising or privacy infringement. Features

Multi Process Compatible
Works on any site or local files opened by the browser (Firefox restricts some functions on some URLs.)
Removes duplicate URLs
Option to filter downloads (v1.3)
Import/Export Preferences (v1.4)
Container Support: New Tab will be opened in the same container (v1.5) (requires cookie permission)

Actions

Rotate Left/Right & 180° (v1.5)
Flip Vertical/Horizontal
Reset
Open Image in New Tab
Copy Image as Data:URI (requires clipboardWrite permission) (v1.5)
Save All Images (v1.1)
Save Selected Images (v1.1)
Open Selected Images in New Tabs (v1.1)
Save All Image Links (v1.1)
Save Selected Image Links (v1.1)
Open Selected Image links in New Tabs (v1.1)
Save All Target Images (from a link) (v1.1)
Save All Target Image Links (from a link) (v1.1)
Save Images from Tabs Left/Right (v1.5)
Save Image Links from Tabs Left/Right (v1.5)
Reload Image/All Images (v1.7)

Permissions Explanation:

Access your data for all websites: Used to get remote Images
Input data to the clipboard: Used to Copy to Clipboard (v1.5)
Download files and read and modify the browser’s download history: Used to download images only
Display notifications to you: Used to inform users