List Indent Level Issue

[kuimnet]

I got an issue regarding to QuillDeltaToHtmlConverter and convert. I was try to add a customCssClasses as a converter option base on the indent. But it was failed to set.

For example I have the following input

[{ insert: 'hello\n\n1st' }, { attributes: { list: 'bullet' }, insert: '\n' }, { insert: '2nd' }, { attributes: { indent: 1, list: 'bullet' }, insert: '\n' }, { insert: '3rd' }, { attributes: { indent: 2, list: 'bullet' }, insert: '\n' }]

Then I go to source code, and make a log on the indent value. It will be always 0. So, it got failed to set.
Is it a bug here, right?

li.item.op.attributes.indent = 0

in
~ line 938 dist/browser/QuillDeltaToHtmlConverter.bundle.js
~ line 157 dist/commonjs/QuillDeltaToHtmlConverter.js
~ line 210 src/QuillDeltaToHtmlConverter.ts

Then I updated to the following code.
li.item.op.attributes.indent = li.item.op.attributes.indent ? li.item.op.attributes.indent : 0

Is the any hazard or risk to the system?

It works, so I can create the custom css classes base on the change.
Meanwhile, it also sets with default class on the list item as ql-indent-1, ql-indent-2, ql-indent-3, etc...

Is it a known issue?