I can confirm this pub is still present in InDesign CC 2019 (14.0.2), and I've already wasted a number of hours because of it (searching for the character style in InDesign, finding that section in the ePub, and manually adding the incorrectly-removed <em></em> tags.)
You can also confirm the bug without having to export—for example (see attached screenshots):
1. Add a character style.
2. Confirm in "Edit All Export Tags" that by default, this character style is set to be included in the HTML and to emit CSS.
3. Open the character style options, then export tagging. Under Tag, select <em>, and uncheck "Include Classes in HTML". The export details now correctly show use of the <em> tag, but incorrectly show an em class, to be added to that <em> tag. According to the Export Details, we should receive code like the following:
>>> 'Twas <em class="em">brillig,</em> and the <em class="em">slithy toves</em>
Which is incorrect, but still usable. Instead, what we receive is:
>>> 'Twas brillig, and the slithy toves
Which reflects neither the options we chose, nor what the Character Style panel suggests that it will output. What is actually desired in this situation is:
>>> 'Twas <em>brillig,</em> and the <em>slithy toves</em>
4. At this point, if you check "Edit All Export Tags", you'll see that the option "Include in HTML" has been unchecked, and the option actually modified in the Character Style Options ("Include Classes in HTML") does not appear at all in the window.
So it sounds like the separate "Include Classes in HTML" and "Include in HTML" options have been conflated somewhere behind-the-scenes, and in addition there seems be be an issue with the display of export details.
As a good deal of work is already required to clean up InDesign's exported ePub into a usable ePub when InDesign is working as-designed, this bug is incredibly frustrating—and should you not notice the missing tags until you've otherwise processed the ePub, fixing it can be mind-numbingly dull and rather time-consuming.
T. Wasser
I can confirm this pub is still present in InDesign CC 2019 (14.0.2), and I've already wasted a number of hours because of it (searching for the character style in InDesign, finding that section in the ePub, and manually adding the incorrectly-removed <em></em> tags.)
You can also confirm the bug without having to export—for example (see attached screenshots):
1. Add a character style.
2. Confirm in "Edit All Export Tags" that by default, this character style is set to be included in the HTML and to emit CSS.
3. Open the character style options, then export tagging. Under Tag, select <em>, and uncheck "Include Classes in HTML". The export details now correctly show use of the <em> tag, but incorrectly show an em class, to be added to that <em> tag. According to the Export Details, we should receive code like the following:
>>> 'Twas <em class="em">brillig,</em> and the <em class="em">slithy toves</em>
Which is incorrect, but still usable. Instead, what we receive is:
>>> 'Twas brillig, and the slithy toves
Which reflects neither the options we chose, nor what the Character Style panel suggests that it will output. What is actually desired in this situation is:
>>> 'Twas <em>brillig,</em> and the <em>slithy toves</em>
4. At this point, if you check "Edit All Export Tags", you'll see that the option "Include in HTML" has been unchecked, and the option actually modified in the Character Style Options ("Include Classes in HTML") does not appear at all in the window.
So it sounds like the separate "Include Classes in HTML" and "Include in HTML" options have been conflated somewhere behind-the-scenes, and in addition there seems be be an issue with the display of export details.
As a good deal of work is already required to clean up InDesign's exported ePub into a usable ePub when InDesign is working as-designed, this bug is incredibly frustrating—and should you not notice the missing tags until you've otherwise processed the ePub, fixing it can be mind-numbingly dull and rather time-consuming.
Thanks.