For (for a while I think) the unit tests (for standalone project) were failing for me in Portugese:
ERROR] Failures:
[ERROR] MorfologikPortugueseSpellerRuleTest.testBrazilPortugueseSpellingCustomReplacements:453->assertSingleError:102->assertErrorLength:65 expected:<1> but was:<0>
[ERROR] MorfologikPortugueseSpellerRuleTest.testPortugueseSpellerAcceptsArbitraryHyphenation:623->assertSingleError:102->assertErrorLength:65 expected:<1> but was:<0>
[ERROR] MorfologikPortugueseSpellerRuleTest.testPortugueseSpellerMultitokens:589->assertErrorLength:65 expected:<2> but was:<1>
...
[INFO] Dutch module for LanguageTool ...................... SUCCESS [ 13.865 s]
[INFO] Portuguese module for LanguageTool ................. FAILURE [01:52 min]
[
I am running on Linux with JDK 17 and just pulled the latest sources in ‘master’ branch