Tried, though because the blanc value it is ignored:
Tried with a ".", works so the getMessage theory is oke.
Only works on SP:
Of course you could also go for editing the Script Include like I described. Though I personally would avoid changing the Script Include if possible (then it's not out-of-the-box anymore and updates from patches/upgrades will ignored).
If my answer helped you in any way, please then mark it as helpful.
Kind regards,
Mark
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