When I tried it in calibre ebook-edit it failed
On the example that has the nested spans, it fails the same as all the other attempts I have tried. I'm going to have to bite the bullet and modify this plugin and try it there.
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Retried with
Code:
<span[^<>]*>((?:(?!<(?:span|/span)).)*)</span>
This matches the 1st and 3rd span's I had above
Code:
<span id="kobo.114.1">I don’t go in for ‘lawn maintenance’, though — all that weeding and feeding.</span>
and
<span id="kobo.114.3"> As Vita Sackville-West said, ‘A weed is only a plant in the wrong place.’ To which we should add: ‘or one for which we haven’t yet discovered the use’.</span>
however on the 2nd span
Code:
<span id="kobo.114.2"> I prefer my ‘weeds’: the clover, which keeps the grass naturally green with its nitrogen-fixing nodules; the daisy, opening and closing each day (its name comes from the Old English <em>daeges <span class="ent1">ē</span>age</em>, meaning ‘the day’s eye’); the little blue-purple <em>Prunella</em>, known as ‘self-heal’, used to treat sore throats, mouth <a id="page_184"></a>ulcers and open wounds — and still used in modern herbal medicine as an astringent for external or internal wounds.</span>
just matches the interior span
Code:
<span class="ent1">ē</span>
Again; this testing is just being done within the confines of ebook-edit