Trilium Notes: Fixing Custom Print Stylesheet Issues

Having trouble getting your custom print stylesheet to work in Trilium Notes? You're not alone! Many users find themselves scratching their heads when their carefully crafted print styles don't seem to apply when exporting to PDF or printing directly. This comprehensive guide dives deep into the potential causes and solutions, ensuring your printed notes look exactly as you intend. Let's get started and make those printouts perfect!

Understanding the Issue: Custom Print Stylesheets in Trilium Notes

So, you've meticulously created a CSS note, tagged it with #appCss, and even nestled your styles within an @media print { ... } block. You've diligently used !important to override default styles and refreshed Trilium Notes with Ctrl+Shift+R. Yet, when you generate a PDF or hit the print button, your custom styles seem to vanish into thin air. What gives?

This issue often arises from a few key factors, particularly with recent updates to Trilium Notes and its printing mechanism. To effectively troubleshoot this, it's crucial to understand how Trilium Notes handles print styles and the potential pitfalls in the customization process.

The core of the problem often lies in how Trilium Notes isolates the printing environment. Recent refactoring, such as the introduction of the /?print route, creates a dedicated space for printing. While this improves print performance and stability, it can also mean that user-defined #appCss notes might not be loaded in this isolated environment. This isolation is designed to ensure a consistent printing experience but can inadvertently prevent custom styles from being applied. Understanding this separation is the first step in resolving the issue.

Another aspect to consider is the specificity of your CSS rules. Even with !important, conflicting styles from Trilium's default stylesheets might override your custom styles if they have higher specificity. This means you need to ensure your selectors are specific enough to target the elements you want to style. Using browser developer tools to inspect the printed output can help you identify which styles are being applied and where conflicts might occur.

Furthermore, syntax errors or incorrect CSS can also prevent your styles from being applied. A small typo in a selector or a missing semicolon can invalidate an entire block of CSS. Always double-check your CSS for errors, and consider using a CSS validator to catch any mistakes.

Finally, the order in which CSS rules are applied matters. If your custom stylesheet is loaded before Trilium's default stylesheets, your styles might be overridden. Trilium Notes typically loads #appCss notes, but there might be nuances in the loading order that affect the final output. Ensuring your styles are loaded last can help mitigate this issue. In the following sections, we'll explore these factors in more detail and provide practical steps to resolve them, ensuring your custom print stylesheets work as expected.

Diagnosing the Problem: Is Your #appCss Note Being Loaded?

Let's dive into the nitty-gritty of diagnosing why your custom print stylesheet might not be working. The first step is to determine whether your #appCss note is even being loaded in the print environment. This might sound technical, but it's a crucial step in pinpointing the root cause of the problem. Think of it like checking if the light switch is even connected before you start troubleshooting the bulb.

One of the most straightforward ways to check this is by adding a simple, highly visible style to your #appCss note within the @media print block. For instance, you could try setting the background color of the entire page to a bright, contrasting color like bright pink. Here’s how you might write the CSS:

@media print {
  body {
    background-color: pink !important;
  }
}

This CSS snippet targets the body element in the print environment and sets its background color to pink. The !important declaration ensures that this style should override any other conflicting styles. After adding this to your #appCss note, refresh Trilium Notes with Ctrl+Shift+R and attempt to print or export to PDF. If the background turns pink in the print preview or exported PDF, your #appCss note is being loaded, and the issue likely lies elsewhere, such as CSS specificity or syntax errors.

However, if the background remains unchanged, it indicates that your #appCss note is not being loaded in the print environment. This could be due to several reasons. As mentioned earlier, recent changes in Trilium Notes' printing mechanism might isolate the print environment, preventing user-defined stylesheets from being loaded by default. In this case, you might need to explore alternative methods of injecting your styles into the print environment, which we'll discuss later in this guide.

Another potential reason for the #appCss note not being loaded is incorrect configuration or placement of the note. Ensure that the note is tagged with #appCss and that it's placed in a location where Trilium Notes can find it. While Trilium Notes typically loads #appCss notes regardless of their location, it's always a good practice to keep them in a dedicated folder for organizational purposes. Additionally, verify that the note is enabled and not accidentally disabled.

By performing this simple test, you can quickly determine whether your #appCss note is being loaded, narrowing down the potential causes of the issue and guiding your troubleshooting efforts. If the note is being loaded, the next step is to examine your CSS for specificity issues and syntax errors. If it's not being loaded, you'll need to explore alternative methods for applying your print styles, which we’ll cover in the upcoming sections.

Resolving CSS Specificity and Syntax Issues

Okay, so you've confirmed that your #appCss note is being loaded, but your custom print styles are still stubbornly refusing to appear. Don't worry, guys, we're getting closer to cracking this! The next step is to dive into the depths of CSS specificity and syntax, two common culprits behind stylesheet woes.

Think of CSS specificity as a hierarchy: some styles are simply more powerful than others. Even with the !important declaration, a more specific CSS rule can override your custom styles. This is a crucial concept to grasp when troubleshooting print stylesheets. For example, a style rule that targets an element by its ID is more specific than a rule that targets it by its class. Similarly, inline styles (styles applied directly to an HTML element) are the most specific of all.

To tackle specificity issues, you need to ensure your CSS selectors are as specific as necessary to target the elements you want to style. Let's say you're trying to change the font size of headings in print. Instead of a general rule like h1 { font-size: 14pt !important; }, try a more specific selector that targets headings within a particular context, such as .note-body h1 { font-size: 14pt !important; }. This ensures that your style only applies to headings within the note body, reducing the chance of conflicts with other styles.

Browser developer tools are your best friends when it comes to inspecting CSS specificity. When you print or export to PDF, use the browser's