Balance des couleurs (TLS) disparu

Obsolete Effects, Transitions and Presets removed

That was in the "obsolete" folder for a reason. And has been for years. With the often-given notice that at some point the obsolete effects would disappear.

They were ancient code, they were not GPU accelerated, and could frequently cause GPU acceleration (usage) to be cut off on other effects on the clip. And ... they were all used by less than 1% of the user base. So they were never going to replace them or rewrite the code.

Mac Silicon users lost those "obsolete" on moving to that new CPU, as those would have requred new code to use them.

And they finally ... like six years after putting them in the Obsolete folder, removed them. With public notice both on this forum and on their blog/info sites.

As you noted, if you copy a sequence with that effect applied into a 25.x project, you can have access to the effect in that project.

Past that, they have a chart with the list of suggested replacements for all Obsolete effects. Including the use of Lumetri's HSL Secondary panel for this one, I believe.