@catch reminded me of this in #1164852-65: Inconsistencies in field language handling → , and it turned out that core uses the wrong operator all over the place.
Attached patch is a quick fix. Note that I only grepped for '!='. I don't think there are any instances of "!=", but there may very well be instances of != in plain db_query*() SQL strings.
For D8+ (separate issue), we should remove support for '!=' from EFQ and also throw an exception in DatabaseCondition::condition() in case $operator == '!=' is passed. (No magic conversion -- otherwise, people won't understand this ever.)
Fixed
7.0 ⚰️
base system
Issue summaries save everyone time if they are kept up-to-date. See Update issue summary task instructions.
Changes an existing API or subsystem. Not backportable to earlier major versions, unless absolutely required to fix a critical bug.
After being applied to the 8.x branch, it should be considered for backport to the 7.x branch. Note: This tag should generally remain even after the backport has been written, approved, and committed.
Not all content is available!
It's likely this issue predates Contrib.social: some issue and comment data are missing.