Why bother installing altsearch, when Regular Expressions don't work?

If I sound facetious, I am. I can find and replace duplicated partagraph marks in Word 2000, but never in OpenOffice and never in Libre Office. The expression displayed, $^ does nothing, finds nothing. In Word 2000, I can find tab characters, paragraph characters, ect ect. Not in Libre Office.
Text editing at this level is fundamental to managing text documents. How can a document program get this so wrong?

Note that the Alternative Find & Replace extension offers greater regular expression capability over that built-in to LO by default. There are numerous examples, on this forum, of answers indicating that the extension can provide solutions to problems that the regular expression engine in LO cannot.

$^ does nothing, finds nothing.

there are propably two reasons,

  1. youre not able to tick the [x]regular Expression-option ;-)
  2. there are no empty paragraphs