Link to issue number:

Fixes #14041

Summary of the issue:

Users may want to see changes included in the current version of add-ons, especially to decide if they want to update them, and to get an idea of new features, bug fixes and so on.

Description of user facing changes:

• In the add-on store, a new action allows to see changes for the current version of add-ons which specify this information.
• In the Updatable add-ons dialog, the virtual list used in other tabs of the store is presented, instead of the old small list, so that the changelog, if available, can be opened from the context menu to decide if add-ons should be updated to the available version.
  List of changes will be shown in browse mode. If changes are writen in markdown, they will be rendered in formatted HTML. The title of that message will show the add-on version name, and buttons will be available to copy the info and close the browseable message.

Description of developer facing changes:

• Add-on models have a new changelog property.
• The self.addonsList of the UpdatableAddonsDialog class is a subclass of the AddonVirtualList.

Description of development approach:

• Created a new action to show the changelog, when available, similar to other actions.
• Added changelog to add-on models.
• In the Updatable add-ons dialog, the same list used in the store dialog is presented, so that changelog can be opened from the context menu.

Testing strategy:

• Add list of changes to manifest.ini and json file corresponding to the urlShortener add-on. Check that changes can be shown from the context menu of the store, and that this action is not available for other add-ons.
• Downgrade version of urlShortener to make an updatable add-on. In source/addonStore/models/addon.py, in the _createStoreCollectionFromJson function, add the following code just for testing:

	for addon in data:
		if addon["addonId"] == "urlShortener":
			addon["changelog"] = "changes"

Check that changelog can be shown just for this add-on.

Also, changelog in markdown has been created in the manifest and in the store collection, to check that markdown is properly rendered in HTML in the store and in the Updatable add-ons dialog.

	changelog = """
* A.
* b
"""
	addonCollection = _createAddonGUICollection()

	for addon in data:
		addon["changelog"] = changelog

Tests have been done with the resourceMonitor add-on to check that the context menu can be used from the Updatable add-ons dialog.

Known issues with pull request:

Sometimes, NVDA says thw word "panel" when the changelog is opened.

Code Review Checklist:

• Documentation:
  • Change log entry
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English
• API is compatible with existing add-ons.
• Security precautions taken.