diff --git a/Cargo.toml b/Cargo.toml
index cba97538..5455ad79 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -152,6 +152,7 @@ tikv-jemallocator = { version = "0.6", features = [
 ], optional = true }
 
 sd-notify = { version = "0.4", optional = true }
+# Used for inspecting request errors
 http-body-util = "0.1.3"
 
 # Used for matrix spec type definitions and helpers
diff --git a/src/api/ruma_wrapper/axum.rs b/src/api/ruma_wrapper/axum.rs
index 73a75b3d..2eb2c7f8 100644
--- a/src/api/ruma_wrapper/axum.rs
+++ b/src/api/ruma_wrapper/axum.rs
@@ -1,4 +1,5 @@
 use std::{collections::BTreeMap, iter::FromIterator, str};
+use std::error::Error as _;
 
 use axum::{
     body::Body,
@@ -60,9 +61,9 @@ where
             )
             .await
             .map_err(|err| {
-                if std::error::Error::source(&err)
+                if err.source()
                     .as_ref()
-                    .and_then(|err| std::error::Error::source(err))
+                    .and_then(|err| err.source())
                     .is_some_and(|err| err.is::<http_body_util::LengthLimitError>())
                 {
                     Error::BadRequest(ErrorKind::TooLarge, "Reached maximum request size")