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userChrome not working

adam.jan.piotrowski
adam.jan.piotrowski
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I would like to customize styling for recurring events in Calendar (115.11.1 on MacOS) without using extensions/add-ons. I enabled userChrome.css (`toolkit.legacyUserProfileCustomizations.stylesheets`) and the “has:” selector (`layout.css.has-selector.enabled`). In my userChrome.css, I added styles: 

   li:has([alt*="Recurring"]) { background-color:grey !important; padding:1rem !important; }
   li:has(*[alt*="Recurring"]) { background-color:yellow !important; padding:1rem !important; }

Unfortunately, this seems to have no effect upon restarting Thunderbird. However, when I open Developer Toolbox (`Tools > Developer Toolbox > Developer Toolbox > Inspector` tab) suddenly everything works and the stylesheets are applied, but only until Thunderbird is shut down. Weirdly, other custom styles in userChrome.css work ok.

Is this intended behavior or a bug?

I would like to customize styling for recurring events in Calendar (115.11.1 on MacOS) without using extensions/add-ons. I enabled userChrome.css (`toolkit.legacyUserProfileCustomizations.stylesheets`) and the “has:” selector (`layout.css.has-selector.enabled`). In my userChrome.css, I added styles: li:has([alt*="Recurring"]) { background-color:grey !important; padding:1rem !important; } li:has(*[alt*="Recurring"]) { background-color:yellow !important; padding:1rem !important; } Unfortunately, this seems to have no effect upon restarting Thunderbird. However, when I open Developer Toolbox (`Tools > Developer Toolbox > Developer Toolbox > Inspector` tab) suddenly everything works and the stylesheets are applied, but only until Thunderbird is shut down. Weirdly, other custom styles in userChrome.css work ok. Is this intended behavior or a bug?

Alle svar (2)

david
david
  • Top 10 Contributor
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I cannot advise on the proper CSS to resolve your issue, but I can advise you that this is not a bug. I say that because use of userChrome.css is not officially supported.

Nyttig?

adam.jan.piotrowski
adam.jan.piotrowski Spørgsmålsstiller
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Thank you for your reply. I do realize that user styling via userChrome is not officialy supported. However, I sucessfully tested the CSS style in Firefox by copying the relevant elements form TB inspector. What is more, my experience with Thunderbird is that userChrome works great in Supernova. What I am trying to understand is the behaviour of some aspects of the style not being applied straight away.

Nyttig?

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