I wrote this Chrome extension. It's very simple (especially the v1 release, only ~700 bytes) and easily customizable through the source code.
It creates an alternative bookmarking mechanism and is probably best used as a temporary holding space because it's faster to use than normal bookmarks.
Successes:
- Gratis
- Windows compatible
- Works offline
Failures:
- Only supports 512 items
- But if you change
chrome.storage.sync
to chrome.storage.local
in the source, you could have unlimited storage.
Other positives:
- There's no possibility for duplication.
- The interface can be tweaked for custom export options.
This Chrome extension will create an additional Add Bookmark button with its own separate storage location.
Ctrl+Shift+A bookmarks the active page.
Ctrl+Shift+E opens the options page.
Press the toolbar button to bookmark the page.
The button disappears on bookmarked pages.
Options Page
- Ctrl+A inverts item selection.
- The options page presents bookmarked URLs as hyperlinks.
- Click/click-twice to select/deselect items.
- Pressing the del key, triggers the delete function of selected items.
- One confirmation dialog will appear before permanent deletion.
- There's an import/export function. It works with item selection. Import works with JSON. Export works with JSON/markdown.
- JSON Format:
{url : {'favicon': faviconurl, 'title': title}}
- There's a delete button.
- There's an invert selection button.
Notes
- I don't think extensions like this should be used for maintaining browsing data. Only for producing quick lists.
- It doesn't have folders.
- I might write a python component that duplicates the extension by changing its name and color scheme, to provide multiple toolbar buttons and a folder type functionality. That's only if the Chrome API doesn't support multiple activepage buttons.
The toolbar button:

The options page:
