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While dragging when the width approaches the default width within 16px (more or less), snap the panel width to the default. When the snapping happens, add an emphasis animation to the resize bar.
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Resizing the LHS
Default channel sidebar width: 240px
For window widths < 820:
not resizable
Touch devices
not resizable
For window widths 821-1199:
min-width = 200px
max-width = 264px
For window widths 1200-1680:
min-width = 200px
max-width = 304px
For window widths > 1680px:
min-width: 200px
max-width: 440px
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