enable setting render text mode to enchanced

[tibor-mirnic]

There is a problem with selecting text in browsers other that Firefox, selection jump to the top/bottom of
the page when cursor moves over white space ( space, paragraph, new line etc. ). I am pretty sure the
problem is with additional div.endOfPage element, only Firefox disables user-select on it.

When you set textLayerMode to 'ENHANCED' then it works as expected.

[sChupin]

I've just tested the three different modes for the introduced [render-text-mode] input and I can't see any difference in the way the text selection is working.

For the three modes (DISABLED, ENABLED and ENHANCED), the text is selectable and the problem discussed in the comment of tibor-mirnic is happening.

Can you explain me what this input is supposed to do? Thank you

[VadimDez]

@sChupin https://github.com/mozilla/pdf.js/blob/b6f58191ca9c35bec4d3646840c7bd37b529ee95/web/pdf_page_view.js#L35-L38

[sChupin]

I still don't get the difference between ENABLED and ENHANCED mode.
I can see in the code of text_layer_builder.js these lines:

if (!this.enhanceTextSelection) {
  let endOfContent = document.createElement('div');
  endOfContent.className = 'endOfContent';
  this.textLayerDiv.appendChild(endOfContent);
}

But I don't see the difference when selecting the text in a PDF. Do you have a use case when this changes the behavior of the selection?