diff --git a/CHANGELOG.md b/CHANGELOG.md
index ff5a52ca..9d97b9bb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+### Removed
+
+## [0.26.4] - 2024-09-08
+
+### Added
+
+### Fixed
+
+* custom flags were not overriding the default, but the other way around.
+
+### Changed
+
 * Made more code public for miri to use
 * Replaced `lazy_static` with std's `OnceLock`
 
diff --git a/Cargo.lock b/Cargo.lock
index 118e12e5..029cb8fc 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -592,7 +592,7 @@ dependencies = [
 
 [[package]]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 dependencies = [
  "annotate-snippets",
  "anyhow",
diff --git a/Cargo.toml b/Cargo.toml
index 2a49de93..980ced71 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "A test framework for testing rustc diagnostics output"
diff --git a/src/parser.rs b/src/parser.rs
index 99bba4cc..26e3d7be 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -453,7 +453,7 @@ impl CommentParser<Comments> {
         }
 
         for (k, v) in base.custom {
-            custom.entry(k).or_insert(v);
+            custom.insert(k, v);
         }
 
         *self.base() = defaults;
diff --git a/tests/integrations/basic-bin/Cargo.lock b/tests/integrations/basic-bin/Cargo.lock
index 3d7d75c7..51ae75e7 100644
--- a/tests/integrations/basic-bin/Cargo.lock
+++ b/tests/integrations/basic-bin/Cargo.lock
@@ -716,7 +716,7 @@ dependencies = [
 
 [[package]]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 dependencies = [
  "annotate-snippets",
  "anyhow",
diff --git a/tests/integrations/basic-fail-mode/Cargo.lock b/tests/integrations/basic-fail-mode/Cargo.lock
index 806d3727..04ef877b 100644
--- a/tests/integrations/basic-fail-mode/Cargo.lock
+++ b/tests/integrations/basic-fail-mode/Cargo.lock
@@ -716,7 +716,7 @@ dependencies = [
 
 [[package]]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 dependencies = [
  "annotate-snippets",
  "anyhow",
diff --git a/tests/integrations/basic-fail/Cargo.lock b/tests/integrations/basic-fail/Cargo.lock
index 1aacb5fe..189d9210 100644
--- a/tests/integrations/basic-fail/Cargo.lock
+++ b/tests/integrations/basic-fail/Cargo.lock
@@ -716,7 +716,7 @@ dependencies = [
 
 [[package]]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 dependencies = [
  "annotate-snippets",
  "anyhow",
diff --git a/tests/integrations/basic-fail/Cargo.stdout b/tests/integrations/basic-fail/Cargo.stdout
index 945ec6dd..c236b8b8 100644
--- a/tests/integrations/basic-fail/Cargo.stdout
+++ b/tests/integrations/basic-fail/Cargo.stdout
@@ -463,6 +463,7 @@ Building aux file tests/actual_tests_bless/auxiliary/the_proc_macro.rs ... ok
 tests/actual_tests_bless/aux_proc_macro_no_main.rs ... FAILED
 tests/actual_tests_bless/compile_flags_quotes.rs ... FAILED
 tests/actual_tests_bless/compiletest-rs-command.rs ... FAILED
+tests/actual_tests_bless/edition_override.rs ... FAILED
 tests/actual_tests_bless/failing_executable.rs ... ok
 tests/actual_tests_bless/failing_executable.rs (revision `run`) ... FAILED
 Building aux file tests/actual_tests_bless/auxiliary/foomp.rs ... ok
@@ -632,6 +633,39 @@ full stdout:
 
 
 
+FAILED TEST: tests/actual_tests_bless/edition_override.rs
+command: "rustc" "--error-format=json" "--out-dir" "$TMP "tests/actual_tests_bless/edition_override.rs" "--extern" "basic_fail=$DIR/tests/integrations/basic-fail/../../../target/$TMP/$TRIPLE/debug/libbasic_fail.rlib" "--extern" "basic_fail=$DIR/tests/integrations/basic-fail/../../../target/$TMP/$TRIPLE/debug/libbasic_fail-$HASH.rmeta" "-L" "$DIR/tests/integrations/basic-fail/../../../target/$TMP/$TRIPLE/debug" "-L" "$DIR/tests/integrations/basic-fail/../../../target/$TMP/$TRIPLE/debug" "--edition" "2018"
+
+error: error pattern found in pass test
+ --> tests/actual_tests_bless/edition_override.rs:6:32
+  |
+6 |         0...10 => {} //~ WARN: deprecated
+  |                                ^^^^^^^^^^ expected because of this annotation
+  |
+ ::: tests/actual_tests_bless/edition_override.rs:2:4
+  |
+2 | //@check-pass
+  |    ^^^^^^^^^^ expected because of this mode change
+  |
+
+full stderr:
+warning: `...` range patterns are deprecated
+ --> tests/actual_tests_bless/edition_override.rs:6:10
+  |
+6 |         0...10 => {}
+  |          ^^^ help: use `..=` for an inclusive range
+  |
+  = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
+  = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
+  = note: `#[warn(ellipsis_inclusive_range_patterns)]` on by default
+
+warning: 1 warning emitted
+
+
+full stdout:
+
+
+
 FAILED TEST: tests/actual_tests_bless/failing_executable.rs (revision `run`)
 command: "$CMD"
 
@@ -1061,6 +1095,7 @@ FAILURES:
     tests/actual_tests_bless/aux_proc_macro_no_main.rs
     tests/actual_tests_bless/compile_flags_quotes.rs
     tests/actual_tests_bless/compiletest-rs-command.rs
+    tests/actual_tests_bless/edition_override.rs
     tests/actual_tests_bless/failing_executable.rs (revision run)
     tests/actual_tests_bless/no_main.rs
     tests/actual_tests_bless/no_main_manual.rs
@@ -1079,7 +1114,7 @@ FAILURES:
     tests/actual_tests_bless/unknown_revision2.rs
     tests/actual_tests_bless/wrong_diagnostic_code.rs
 
-test result: FAIL. 23 failed; 25 passed; 3 ignored
+test result: FAIL. 24 failed; 25 passed; 3 ignored
 
 Building dependencies ... ok
 tests/actual_tests_bless_yolo/revisions_bad.rs (revision `foo`) ... ok
diff --git a/tests/integrations/basic-fail/tests/actual_tests_bless/edition_override.rs b/tests/integrations/basic-fail/tests/actual_tests_bless/edition_override.rs
new file mode 100644
index 00000000..6be60174
--- /dev/null
+++ b/tests/integrations/basic-fail/tests/actual_tests_bless/edition_override.rs
@@ -0,0 +1,9 @@
+//@edition:2018
+//@check-pass
+
+fn main() {
+    match 42 {
+        0...10 => {} //~ WARN: deprecated
+        _ => {}
+    }
+}
diff --git a/tests/integrations/basic-fail/tests/actual_tests_bless/edition_override.stderr b/tests/integrations/basic-fail/tests/actual_tests_bless/edition_override.stderr
new file mode 100644
index 00000000..081fa3d6
--- /dev/null
+++ b/tests/integrations/basic-fail/tests/actual_tests_bless/edition_override.stderr
@@ -0,0 +1,12 @@
+warning: `...` range patterns are deprecated
+ --> tests/actual_tests_bless/edition_override.rs:6:10
+  |
+6 |         0...10 => {}
+  |          ^^^ help: use `..=` for an inclusive range
+  |
+  = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
+  = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
+  = note: `#[warn(ellipsis_inclusive_range_patterns)]` on by default
+
+warning: 1 warning emitted
+
diff --git a/tests/integrations/basic/Cargo.lock b/tests/integrations/basic/Cargo.lock
index 1ea5665c..89d3a5de 100644
--- a/tests/integrations/basic/Cargo.lock
+++ b/tests/integrations/basic/Cargo.lock
@@ -639,7 +639,7 @@ dependencies = [
 
 [[package]]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 dependencies = [
  "annotate-snippets",
  "anyhow",
diff --git a/tests/integrations/cargo-run/Cargo.lock b/tests/integrations/cargo-run/Cargo.lock
index 3d7d75c7..51ae75e7 100644
--- a/tests/integrations/cargo-run/Cargo.lock
+++ b/tests/integrations/cargo-run/Cargo.lock
@@ -716,7 +716,7 @@ dependencies = [
 
 [[package]]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 dependencies = [
  "annotate-snippets",
  "anyhow",
diff --git a/tests/integrations/dep-fail/Cargo.lock b/tests/integrations/dep-fail/Cargo.lock
index 0e7dc0ff..ba44c065 100644
--- a/tests/integrations/dep-fail/Cargo.lock
+++ b/tests/integrations/dep-fail/Cargo.lock
@@ -565,7 +565,7 @@ dependencies = [
 
 [[package]]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 dependencies = [
  "annotate-snippets",
  "anyhow",
diff --git a/tests/integrations/ui_test_dep_bug/Cargo.lock b/tests/integrations/ui_test_dep_bug/Cargo.lock
index 2c989214..2c42a3f0 100644
--- a/tests/integrations/ui_test_dep_bug/Cargo.lock
+++ b/tests/integrations/ui_test_dep_bug/Cargo.lock
@@ -570,7 +570,7 @@ dependencies = [
 
 [[package]]
 name = "ui_test"
-version = "0.26.3"
+version = "0.26.4"
 dependencies = [
  "annotate-snippets",
  "anyhow",