* Remove an obsolete variable - `$MessageTimestamp_width_hover`
Added by 9b54aba4c0
Deprecated 5343be7814
* Replace a variable with a custom property - $MessageTimestamp_width
* Merge with an existing property in :root
rename
* Manage the variable on _MessageTimestamp.pcss
* Replace a Sass variable with a CSS custom property - $container-gap-width
* Replace a Sass variable with a CSS custom property - $container-border-width