Global terms was a feature from the WordPress MU days where multisite and single site installs used different code bases.
In WordPress 3.0, WordPress MU was merged into one location and the UI [14854] and “on” switch [14880] for global terms were completely removed.
Even before this merge, global terms was bug infested and unreliable. After [14854]/[14880], the feature was no longer maintained and became increasingly broken as taxonomies progressed without it (term splitting and term meta do not work at all). At this point, the feature has not worked in 12+ years and there’s no hope for saving it.
This deprecates the remaining global terms related code and no-ops the functions.
Global terms, you don’t have to go home, but you can’t stay here.
Props scribu, wonderboymusic, SergeyBiryukov, nacin, pento, desrosj, johnjamesjacoby, johnbillion, dd32.
Fixes#21734.
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git-svn-id: http://core.svn.wordpress.org/trunk@53799 1a063a9b-81f0-0310-95a4-ce76da25c4cd
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