Any HTML editor would do including notepad, but I want to suggest something better. HTML help was added in WFA in 2.2 about 2 years ago, but this manual task is too tidious for people to use this feature.
If you have a constant template layout for how your HTML doc should look like, then I had created a workflow which does everything for you.
You just need to execute the workflow and provide the doc contents as User-Inputs like
1. Workflow Name
2. Workflow Description.
3. User-Input and teir description. Images you want to add
4. Expected output
5. Notes you want to add
The result will give you a formatted CSS styled HTML zipped with all your images and everything . All within 1-2 seconds. The zip file can be directly uploaded into WFA workflow. That's all.
The only time you spend is deciding what you want to document.
You want to give it a try?
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