How about this automation script solution?
(example for work log)
AUTOMATION SCRIPT
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AUTOSCRIPT: WLDESC
DESCRIPTION: WORKLOG - Add description from long_description
LANG: python
code:
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from psdi.mbo import MboConstants
from psdi.mbo import MboSet
from psdi.util import HTML
worklog = mbo.getThisMboSet()
if(worklog is not None and worklog.getMboValueData("DESCRIPTION").isNull()):
descriptionLongDescription = HTML.toPlainText(worklog.getString("DESCRIPTION_LONGDESCRIPTION"))
description = descriptionLongDescription[0:99]
worklog.setValue("DESCRIPTION", description, MboConstants.NOACCESSCHECK)
---------------
LAUNCHPOINTNAME: WLDESC
OBJECT: WORKLOG
Event: Save , Add, Before Save
=====================================
enter long text to long_description field and save SR.

Result

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Jan Ondrušek
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