About this extension

Scratchpad provides an environment to experiment with JavaScript in Firefox. The item on the browser's Tools menu opens one or more separate windows which allow writing and running code that interacts with the active tab in the topmost window, in either the normal page context or Scratchpad's content context for the tab (with some limits) or in Scratchpad's background context.

Scratchpad uses CodeMirror 5, Copyright © Marijn Haverbeke and others. CodeMirror is released under the MIT License.

Developer comments

Notes on the permissions which Scratchpad uses:

"Open File ..." is really upload (i.e., load from disk).
"Save" and "Save As ..." are really download (i.e., save to disk). Scratchpad uses the Downloads permission for this reason. The extension Downloads API provides more functionality than HTML download, like feedback on whether the "save" was successful or not.
Scratchpad uses the Menus permission to add an item to the Tools menu.
Scratchpad uses the Storage permission to persist user preferences over time.
Scratchpad uses the <all_urls> permission to access all sources in all tabs to inject JavaScript, its core function.
Users can enable optional permissions as necessary for the code they write and run in Scratchpad.

Users who have Google Safe Browsing enabled will have network activity when saving files. Scratchpad itself never makes any network connection and sends no information anywhere. Users who don't wish to use Google Safe Browsing can disable it in the "Privacy & Security" tab of Firefox settings under "Deceptive Content and Dangerous Software Protection."

In no particular order, features I currently intend to add eventually include:

More CodeMirror features enabled (The extension validator rejects a lot of it, so there could be some patching involved.)
Per-scratchpad settings

From the statistics pages, the oldest FF versions seen as users:

FF 72 on 31 Mar 2023 through 8 May
FF 79 on 8 Jan 2023 (then never again)
FF 84 on 21 Feb 2023 through 4 Jun

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This add-on needs to:

Download files and read and modify the browser’s download history
Access your data for all websites

This add-on may also ask to:

Read and modify bookmarks
Read and modify browser settings
Get data from the clipboard
Input data to the clipboard
Open files downloaded to your computer
Read the text of all open tabs
Access your location
Access browsing history
Display notifications to you
Hide and show browser tabs
Access browser tabs
Access browsing history
Access browser activity during navigation

Release notes for 0.7.1

Release notes for 0.7.1
Bug fix: lack of user activation can block open picker
Bug fix: button bar keeps focus when it shouldn't
Bug fix: special keys matching [PRS] handled incorrectly
Bug fix: incomplete descriptions (about) for permissions
Map Ctrl-O same as the "Open File ..." button
Focus editor cursor on pointer entry

Release notes for v0.7
Bug fix: count tabs correctly
Bug fix: 1px font size error at startup
Tab key obeys space/tab preference (default keymap)
Shift-Tab outdents instead of autodents (default keymap)
Remap Ctrl+[JOPRS] to prevent browser defaults
* Ctrl-P prints the code frame
* Ctrl-R same as the "Run" button
* Ctrl-S same as the "Save As ..." button

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