Added SHIFT kbd explicitly

[t-powers]

SHIFT + ! , TAB

Because

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Issue

Closes #XXXXX

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[t-powers]

Added SHIFT kbd explicitly to show button is needed to be pressed with ! then followed by TAB.

[MaoShizhong]

Shift isn't necessary to include here because what matters is the ! character, not the keys pressed to produce it. <kbd>!</kbd> means "whatever produces !" and for some people, that may not include shift.