When using a different keyboard layout (i.e. AZERTY (see attachment)), the in-game commands cannot be executed without typing the corresponding place of the letters in QWERTY.
For example, to reload the chunks (with F3+A), the A in QWERTY is located at the Q of AZERTY (they are inverted) so, F3+Q needs to be typed in AZERTY (instead of F3+A).
This is also the case for typing in chat or command blocks. For example, to select all the text (with crtl+A), AZERTY users have to type crtl+Q instead.
It may be difficult to understand so, in a nutshell, people using a different keyboard layout have to type the commands as if they had a QWERTY keyboard.
The versions prior to 1.13 were not affected.
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We're tracking this issue in MC-121278, so this ticket is being resolved and linked as a duplicate.
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