About tab stops
Tab stops are converted to <span class="role-tab"> </span>. These span elements are processed as follows:
When generating styled HTML (that is, XHTML+CSS), some JavaScript™ code (w2x_install_dir/xed/expand-tabs.js) is added to the output file. This code computes and gives a width to all <span class=”role-tab> </span>. This allows to decently emulate tab stops in any modern Web browser.
If you don't want this code to be added to the output file, pass option -p edit.do.expand-tabs "" to w2x.
When generating semantic XHTML and all the other semantic XML formats (DocBook, DITA, etc), it's possible to convert consecutive paragraphs containing text runs aligned on tab stops to a borderless table.
However because, in the general case, it's not possible to emulate tab stops using tables, this XED script is disabled by default. If you really want to emulate tab stops using tables, pass option -p edit.convert-tabs.to-table yes to w2x.