Hi Radha Krishna,
Currently only supports the basic html tags and not custom one. Verify html serializer/processor /at libs/cq/ui/widgets/source/widgets/form/rte . This basically means that unsupported HTML that was entered will get stripped/removed.
As a workaround, i will suggest that you create a custom plain HTML component that is suitable for your use case and not use the Richtext. Another possibility is to create a new plugin to support such a use case.
Thanks,
Sham
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