It appears that the "Streamline" control you're looking for in Procreate 5.3.14 under the stroke properties might not be visible for a few reasons. Here’s a detailed summary of the information gathered from several resources that may help you resolve this issue.

1. Brush Settings Navigation: One common reason for the Streamline option being hidden is that the brush settings panel occasionally opens scrolled down, which can result in important controls being out of view. To rectify this, try pulling down on the brush settings panel while you are in the Stroke tab. This can help bring the Streamline setting back into view (source: Procreate Folio).

2. Compatibility with iPad OS: If you have ensured that you're using the latest version of Procreate and have rebooted your iPad, there’s still a possibility that system compatibility issues may arise with certain iPad OS versions. Make sure that your iOS version is up to date to avoid any discrepancies (source: Procreate Folio).

3. Presence in Previous Versions: Another point to be aware of is that some users have reported inconsistencies in the availability of the Streamline feature across different versions of Procreate. Although it should generally be located in the Stroke tab under Stroke Properties, users have encountered cases where it was simply missing (source: Reddit).

4. Tutorial Differences: If you are referencing a tutorial video that showcases the Streamline feature, ensure that the version of Procreate used in that video matches your current version. There could be changes in later updates or differences in brush settings that might mean features are organized differently.

In summary, if you can't find Streamline control, check the visibility of your brush settings panel, ensure your iOS is up to date, and verify that your version aligns with any tutorials you’re referring to. If these steps do not resolve the issue, you may want to reach out to Procreate support or community forums for further assistance.

Sources

Streamline Not Showing in Stoke Prop.Streamline option missing : r/ProCreate - RedditWhere is streamline in Procreate? (smooth lines) - YouTubeNo more Streamline with 4? - Procreate FolioHelp with brushes - Procreate FolioNo more Wobbly Strokes in Procreate [2023] #iPadCalligraphy ...Last part of lines are disappearing - Procreate Folio

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