I understand why it is important for documents to be secured. Is it possible to introduce a way of annotating a 'Secured' document? The resulting file will be a PDF file not searchable but text highlight will be possible.
This will also highlight over the character itself and the effect is not as good as the real Highlight. If you are not satisfied with the color and opacity then right click the rectangle, click Properties and change its appearance. Draw a rectangle around the text you want to highlight.Click on Change Line Thickness tool and set to 0 pt,.Click on Change Color tool, choose the color and set opacity to about 40%,.Click on Comment icon to enable the tools.
In Adobe Acrobat Reader DC two workarounds can be used:
