MarkdownPreview should scroll to top after selecting another note, also fix #3023

[hikerpig]

Description

This PR contains two commits modifying the MarkdownPreview component.

• 6438ff6 Mainly trying to fix MD editor scrolls to the top whenever I add new content #3023, but I guess there might be some more issues related.

• 81e8f24 aims to improve performance by eliminating redundant calls.

About the (not added) test

I tried to write some tests for MarkdownPreview component with jest, but got error from @rokt33r/js-sequence-diagrams package.

 FAIL  tests/components/MarkdownPreview.test.js
  ● Test suite failed to run

    TypeError: _.isEmpty is not a function

      at node_modules/@rokt33r/js-sequence-diagrams/dist/sequence-diagram-min.js:8:24486
      at Object.<anonymous> (node_modules/@rokt33r/js-sequence-diagrams/dist/sequence-diagram-min.js:8:25685)
      at Object.<anonymous> (browser/components/MarkdownPreview.js:47:27)
      at Object.<anonymous> (tests/components/MarkdownPreview.test.js:11:24)

Guess the test should be added after this is fixed.

Issue fixed

• MD editor scrolls to the top whenever I add new content #3023
• Preview scrollbar changes position so that entered text is not visible #3047 highly possible
• Editor scrolls to top after generating plantuml diagram #2038 possible

Type of changes

• 🔘 Bug fix (Change that fixed an issue)
• 🔘 Improvement (Change that improves the code. Maybe performance or development improvement)

Checklist:

• 🔘 My code follows the project code style
• 🔘 All existing tests have been passed

---

IssueHunt Summary

Referenced issues

This pull request has been submitted to:

• #3023: MD editor scrolls to the top whenever I add new content
• #2038: Editor scrolls to top after generating plantuml diagram

---

IssueHunt has been backed by the following sponsors. Become a sponsor

[Flexo013]

This might also fix #2886 partially.

[ZeroX-DG]

LGTM 🎉

[ZeroX-DG]

@hikerpig I think your PR can also fix this issue, please also submit your PR there so that after we confirm with the issue author you can claim your reward:
https://issuehunt.io/r/BoostIO/Boostnote/issues/2038

[hikerpig]

@ZeroX-DG Thanks a lot 🍻 .