Note that the Links' attributes are modified in Preview mode on purpose. This way clicking on them will not trigger any functionality and if it happens that a link is being opened it will be opened in a new tab. This is done by getting the onClick and target attributes, preserving the value with custom attributes re_onclick and re_target. When passing again to Design mode, the correct attributes are being returned to their original values.
You can overview them mentioned behavior with this screencast
, in which I am using Firefox and teh dev toolbar to investigate the results from switching to Preview and Design mode.
Note that submitting or using the content removes these custom attributes and all links should be correctly formed.
If it happens that I am mislead on the occurred problem, please open a proper support ticket with more details on the issue and exact steps, so that we could investigate the problem and assist you on this.
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