Sorry I am not a developer and do not speak Polish. Do any of these or the linked information help:

• https://developer.mozilla.org/en-US/docs/CSS/CSS_Reference/Mozilla_Extensions
• https://developer.mozilla.org/en-US/docs/Firefox_16_for_developers

You need to use transition without the -moz prefix in current Firefox version (use both to include support for older Firefox versions).

• https://developer.mozilla.org/en/CSS/transition

Does not work on Firefox 16.0.1 code for the image:

• "-moz-transition: all .2 s linear;".

I tried without the "-moz" and each function separately:

• "-moz-transition-property: all;"
• "-moz-transition-duration: .2 s;"
• "-moz-transition-timing-function: linear;"

and still does not work.

You posted code with a -moz prefix.

Did you also try transition: all .2s linear; (there shouldn't be a space .2s)

See also:

• https://developer.mozilla.org/en-US/docs/CSS/Using_CSS_transitions