[Users] No longer working: Extended search - whole word

[Victoria S.]

Over the weekend I upgraded from Ubuntu 12.04.3 LTS >> Ubuntu 14.04 LTS.  After reinstalling Claws Mail, I noticed that my whole-word search no longer works; for example

s breast & s \\bstem\\b & s canc

previously worked (executed on my Sent mail folder, that contains messages e.g., containing "breast cancer stem cells" in the Subject line.

This search now fails.

I tried various other regex variations (e.g. \bstem\b, /\bstem/\b,  (\W|^)stem(\W|$), /^stem$/, etc.

Can anyone offer a solution?

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