I understand that the word used in the tooltip is "stack" and that could be stated as reasoning why it's not shown on non-stack inserters. However, all inserters end up moving a "stack" (up to three) in later technology research.
Various weapons also show their research-based improvements in the tooltips.
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[Genhis] [1.1.46] Inserter hand stack size missing from non-stack inserters' tooltips
[Genhis] [1.1.46] Inserter hand stack size missing from non-stack inserters' tooltips
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- factorio_bug_inserter_tooltip2.png (72.64 KiB) Viewed 2748 times
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- factorio_bug_inserter_tooltip.png (157.2 KiB) Viewed 2748 times
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Re: [Genhis] [1.1.46] Inserter hand stack size missing from non-stack inserters' tooltips
Thanks for the report. The issue is now fixed for the next release.