Re #1164: Add hidden 'batch_id' value.
(grafted from dd7555fea1198523ae87ea50b32e0935b4db1d2b)

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extra : source : dd7555fea1198523ae87ea50b32e0935b4db1d2b
Fix all buttons on single batch screen (fixes #1164 and #1163).
(grafted from 1f2f414c60bf743a431bf71f0f25ddc188534b6a)

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extra : source : 1f2f414c60bf743a431bf71f0f25ddc188534b6a