Bookmark feature

[tsanie]

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PR Type

What kind of change does this PR introduce?

• Bugfix.
• Feature.
• Code style update (formatting, local variables).
• Refactoring (no functional changes, no api changes).
• Build related changes.
• CI related changes.
• Documentation content changes.
• Other... Please describe:

What is the new behavior?

Bookmark is a plugin that allow the users save their reading position. (using window.localStorage)

The users could just click the bookmark icon (like 🔖) in left-top of the page to save the position.

And when they visit your blog in the next time, they can continue the last reading position by clicking the bookmark icon from the home page.

• Screens with this changes:
  On the left-top of the page: → mouse over →

  When you click it:

  • In the post page: it will save the current scroll position of the current page. (If the bookmark.save have been set to 'auto', it is no need to manual click it.)

  • In the other page: it will take you to the last page you have read, and scroll to the last reading position.

  The icon will not appear in the mobile layout, but the function is well working: if you enter a page, the reading position will be automatically loaded.

• Link to demo site with this changes: https://tsanie.us

How to use?

In NexT _config.yml:

bookmark:
  enable: true
  save: auto # or manual

Does this PR introduce a breaking change?

• Yes.
• No.

[sli1989]

May I ask what's the difference between bookmark and save_scroll: true?

[tsanie]

@sli1989 feature acts the same thing. There is a little difference between them such as localStorage/cookie, and allow you to choose auto or manual save the scroll position by click the bookmark icon.

[ivan-nginx]

We talk about it with @tsanie and i think save_scroll will be removed in next versions.

[stevenjoezhang]

save_scoll refactored in #1049
Now they both use localStorage and have almost the same feature.
Maybe we can combine these two plugins - or make bookmark a built-in component of NexT