Translation from https://cs.wikipedia.org/wiki/Wikipedie:Pod_l%C3%ADpou_(technika)#Odkazy_na_neexistuj%C3%ADc%C3%AD_port%C3%A1ly:
Some talk pages (for example, Diskuse:Večerní univerzita marxismu-leninismu or Diskuse:Mluvnický pád) invite users with new topic tool to create a discussion, even though the talk page exists. By deduction, I determined it's caused by the pages not containing an up-to-date signature, but some older one (neither [ reply ] buttons after the comments are displayed), and not containing a header simultaneously. I believe this is an error since this invitation is missing on some other, sometimes smaller, talk pages (e.g., Diskuse:Velká růžová plavba teplého Ala). --David V.
