Can't use "/" (slash) character in a pattern

[Khotul]

Trying to make a pattern that uses two placeholder variables, with a slash character separating them

pattern: "[papi:player_health_rounded]/[papi:player_max_health_rounded]"

However it results in an error

this placeholder not found: [papi
(full stack trace at the bottom)

As far as I know, double slash (//) is used for dividing, but I don't want to divide, I want a displayable slash character.
I tried escaping it with a backslash \ \/ but it doesn't work sadly.

It works when I replace slash with another character, for example the letter M.
pattern: "[papi:player_health_rounded]M[papi:player_max_health_rounded]"

Full stacktrace of the error:

[18:21:48 INFO]: [BetterHud] Reloading HudManagerImpl...
[18:21:48 WARN]: [BetterHud] Stack trace:
[18:21:48 WARN]: [BetterHud] java.lang.RuntimeException: this placeholder not found: [papi
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.manager.PlaceholderManagerImpl.find(PlaceholderManagerImpl.kt:260)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.manager.PlaceholderManagerImpl.parse(PlaceholderManagerImpl.kt:317)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.renderer.TextRenderer.<init>(TextRenderer.kt:47)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.hud.HudTextParser.<init>(HudTextParser.kt:113)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.hud.HudParser.<init>(HudParser.kt:26)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.hud.HudImpl.elements$lambda$6(HudImpl.kt:59)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.FilesKt.mapSubConfiguration(Files.kt:46)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.hud.HudImpl.<init>(HudImpl.kt:45)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.manager.HudManagerImpl.reload$lambda$2$lambda$1$lambda$0(HudManagerImpl.kt:26)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.MapsKt.putSync(Maps.kt:6)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.manager.HudManagerImpl.reload$lambda$2$lambda$1(HudManagerImpl.kt:25)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.FunctionsKt.runWithExceptionHandling(Functions.kt:31)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.manager.HudManagerImpl.reload$lambda$2(HudManagerImpl.kt:24)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.YamlsKt.forEachAllYaml$lambda$6$lambda$5(Yamls.kt:55)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.FunctionsKt.runWithExceptionHandling(Functions.kt:31)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.YamlsKt.forEachAllYaml$lambda$6(Yamls.kt:52)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.FilesKt.forEachAllFolder(Files.kt:30)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.FilesKt.forEachAllFolder$lambda$5(Files.kt:28)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.FilesKt.forEach(Files.kt:50)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.FilesKt.forEachAllFolder(Files.kt:27)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.YamlsKt.forEachAllYaml(Yamls.kt:50)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.manager.HudManagerImpl.reload(HudManagerImpl.kt:23)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.BetterHudImpl$reload$result$1.get$lambda$4(BetterHudImpl.kt:118)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.util.FunctionsKt.runWithExceptionHandling(Functions.kt:31)
        at BetterHud-bukkit-1.11.3.jar//kr.toxicity.hud.BetterHudImpl$reload$result$1.get(BetterHudImpl.kt:111)
        at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1768)
        at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.exec(CompletableFuture.java:1760)
        at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:387)
        at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1312)
        at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1843)
        at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1808)
        at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:188)```

[toxicity188]

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