Making Plugins (mermaid, datatables) Default

[Tim-Siu]

Please confirm that you have searched existing issues in the repo

Yes, I have searched the existing issues

Any related issues?

No response

What is the area that this feature belongs to?

Performance, Plugins

Is your feature request related to a problem? Please describe.

Currently, the mermaid and datatables plugins are not activated by default. The arguments are that the performance overhead brought in is not negligible:

1. For the mermaid plugin (Add Mermaid Plugin #2475), the external javascript loaded from CDN comes in at 3.3MB and is kind of heavy. It may result in some network costs.
2. For the dataTable plugin (Add dataTable plugin #2446), the javascript involved is much lighter. The performance overhead, however, is not thoroughly investigated.

However, such a configuration is contradictory to our wishes that 'everything works out of the box'. This issue is the umbrella issue to call for investigation on the performance overhead of the plugins and efforts to make the plugins default.

Describe the solution you'd like

It is suggested by Prof. Damith that we can load the javascript libraries on demand. This is possible with modifications to the backend (site build) code.

Describe alternatives you've considered

No response

Additional context

No response