* Move MarkdownPreviewHandler from WebBrowser to WebView2
* Disable context menu
Open links in default browser
* Update expect.txt
* Move SvgPreviewHandler from WebBrowser to WebView2
* Migrate SvgThumbnailProvider from WebBrowser to WebView2
* Migrate CustomControlTest to WebView2
Remove WebBrowser related stuff
* Update tests
* Revert GetThumbnail return value
Disable javascript dialogs in WebView2 for Svg thumbnail and preview
* expect.txt
* Increase timeout for Markdown tests
* Add sleeps
* Add zero check
## Summary of the Pull Request
This PR enables user to preview PDF files in the Explorer preview pane
and in Outlook.
**What is this about:**
Windows does not support out of the box experience for previewing PDF
files in the preview pane. Users need to install third-party software
like Adobe Acrobat reader. The PdfPreviewHandler module enbales the user
to preview PDF files.
**How does someone test / validate:**
Run the installer, open Explorer and select a PDF file, enable the
preview pane. Maybe need to remove third-party PDF software.
## Quality Checklist
- [X] **Linked issue:** #3548
- [ ] **Communication:** I've discussed this with core contributors in the issue.
- [X] **Tests:** Added/updated and all pass
- [X] **Installer:** Added/updated and all pass
- [X] **Localization:** All end user facing strings can be localized
- [ ] **Docs:** Added/ updated
- [x] **Binaries:** Any new files are added to WXS / YML
- [ ] No new binaries
- [x] YML for signing
- [x] WXS for installer
