Requires the library mod Collective.
Creative Block Replacer is a minimalistic mod which allows easy switching in between placing and replacing blocks in creative mode, speeding up the creative process.
To toggle in between block replacing mode:
Sneak three times while remaining in the same position
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When replacing block mode is enabled, right-clicking a block will result in the target block being replaced with the item in hand:
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You may freely use this mod in any modpack, as long as the download remains hosted within the Modrinth ecosystem.
Serilum.com contains an overview and more information on all mods available.
Comments are disabled as I'm unable to keep track of all the separate pages on each mod.
For issues, ideas, suggestions or anything else there is the Github repo. Thanks!