Why does "Paste" work from Thunderbird, but not "Paste Special"?

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I can copy and paste text from any source and insert it in Writer by using Paste (Ctrl+V).

However, copy and paste using Paste Special (Shift+Ctrl+V) does not work for some sources. For example, I can insert text from a BBC article, but not from a Thunderbird email.

I would be grateful for any advice.

Thanks.

Added: I’ve just noticed that if I cut the text that was inserted using Paste, I can immediately paste using Paste Special.
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Paste-Special is a collaboration between two (in this case, separate) entities. One of those entities is the content provider, which performs the copying (or cutting), whilst LO does the pasting. What is causing you confusion is that the only function guaranteed during the cut/copy function is to copy plain-text (mime: text/plain), whilst LO performs the possibility to paste very much more than that, but only if other MIME-types (“Multipurpose Internet Mail Extensions”) are available. If the content-provider does not supply multiple mime-types then LO cannot offer to paste them.

Cut, Copy + Paste: Wikipedia (simple)
MIME Types: Mozilla (complex)

The different options offered are actually each of the MIME types placed into the clipboard by the content provider.

Here is a live demo using this page & Thunderbird:

Copy from this page:

Options offered within LO:

  • Unformatted text :: text/plain
  • HyperText Markup Language (HTML) :: text/html

Copy from Thunderbird:

Options offered within LO:

  • Unformatted text :: text/plain
  • HyperText Markup Language (HTML) :: text/html

So, in this instance the options are identical, but again: the only guarantee during the cut/copy function is to copy plain-text into the clipboard.