JDK-8351996 updated `ClassValue` in JDK 25 to make it more robust in various threading conditions. Unfortunately, this update caused `ClassValue.get` to run more slowly after a call to `ClassValue.remove`. Most applications do not use `ClassValue` directly, but libraries which call both `ClassValue.get` and `remove` may be affected by the slowdown. An example of a library affected by the slowdown is the standard library in Scala 2.12. The slowdown is fixed in in JDK-8358535.