diff --git a/cgi/suggest.pl b/cgi/suggest.pl
index fb59a76e26a5b..d014ef205a7e8 100644
--- a/cgi/suggest.pl
+++ b/cgi/suggest.pl
@@ -47,7 +47,7 @@
 # The API accepts a string input in the "string" field or "term" field.
 # - term is used by the jquery Autocomplete widget: https://api.jqueryui.com/autocomplete/
 # Use "string" only if both are present.
-my $string = decode("utf8", (request_param($request_ref, 'string') || request_param($request_ref, 'term')));
+my $string = request_param($request_ref, 'string') || request_param($request_ref, 'term');
 
 # /cgi/suggest.pl supports only limited context (use /api/v3/taxonomy_suggestions to use richer context)
 my $context_ref = {country => $request_ref->{country},};
diff --git a/lib/ProductOpener/APITaxonomySuggestions.pm b/lib/ProductOpener/APITaxonomySuggestions.pm
index ce7eb027f39d8..a44d580310f5a 100644
--- a/lib/ProductOpener/APITaxonomySuggestions.pm
+++ b/lib/ProductOpener/APITaxonomySuggestions.pm
@@ -80,14 +80,14 @@ sub taxonomy_suggestions_api ($request_ref) {
 	# The API accepts a string input in the "string" field or "term" field.
 	# - term is used by the jquery Autocomplete widget: https://api.jqueryui.com/autocomplete/
 	# Use "string" only if both are present.
-	my $string = decode("utf8", (request_param($request_ref, 'string') || request_param($request_ref, 'term')));
+	my $string = request_param($request_ref, 'string') || request_param($request_ref, 'term');
 
 	# We can use the context (e.g. are the suggestions for a specific product sold in a specific country, with specific categories etc.)
 	# to rank higher suggestions that are popular for similar products
 	my $context_ref = {
 		country => $request_ref->{country},
-		categories => decode("utf8", request_param($request_ref, "categories")),    # list of product categories
-		shape => decode("utf8", request_param($request_ref, "shape")),    # packaging shape
+		categories => request_param($request_ref, "categories"),    # list of product categories
+		shape => request_param($request_ref, "shape"),    # packaging shape
 	};
 
 	# Options define how many suggestions should be returned, in which format etc.
diff --git a/lib/ProductOpener/Display.pm b/lib/ProductOpener/Display.pm
index 90d0d6bd2e1c7..5e2c3df127bb0 100644
--- a/lib/ProductOpener/Display.pm
+++ b/lib/ProductOpener/Display.pm
@@ -200,7 +200,7 @@ use boolean;
 use Excel::Writer::XLSX;
 use Template;
 use Devel::Size qw(size total_size);
-use Data::DeepAccess qw(deep_get);
+use Data::DeepAccess qw(deep_get deep_set);
 use Log::Log4perl;
 use LWP::UserAgent;
 
@@ -529,7 +529,13 @@ A scalar value for the parameter, or undef if the parameter is not defined.
 =cut
 
 sub request_param ($request_ref, $param_name) {
-	return (scalar param($param_name)) || deep_get($request_ref, "body_json", $param_name);
+	my $cgi_param = scalar param($param_name);
+	if (defined $cgi_param) {
+		return decode utf8 => $cgi_param;
+	}
+	else {
+		return deep_get($request_ref, "body_json", $param_name);
+	}
 }
 
 =head2 init_request ()
@@ -4202,16 +4208,16 @@ HTML
 
 	foreach my $tag_ref (@{$request_ref->{tags}}) {
 		if ($tagtype eq 'users') {
-			param('creator', $tagid);
+			deep_set($request_ref, "body_json", "creator", $tagid);
 		}
 		else {
 			my $field_name = $tag_ref->{tagtype} . "_tags";
-			my $current_value = param($field_name);
+			my $current_value = deep_get($request_ref, "body_json", $field_name);
 			my $new_value = ($tag_ref->{tag_prefix} // '') . ($tag_ref->{canon_tagid} // $tag_ref->{tagid});
 			if ($current_value) {
 				$new_value = $current_value . ',' . $new_value;
 			}
-			param($field_name, $new_value);
+			deep_set($request_ref, "body_json", $field_name, $new_value);
 		}
 	}
 
@@ -4291,6 +4297,25 @@ HTML
 	return;
 }
 
+=head2 display_list_of_tags ( $request_ref, $query_ref )
+
+Return an array of names of all request parameters.
+
+=cut
+
+sub list_all_request_params ($request_ref) {
+
+	# CGI params (query string and POST body)
+	my @params = multi_param();
+
+	# Add params from the JSON body if any
+	if (defined $request_ref->{body_json}) {
+		push @params, keys %{$request_ref->{body_json}};
+	}
+
+	return @params;
+}
+
 =head2 display_search_results ( $request_ref )
 
 This function builds the HTML returned by the /search endpoint.
@@ -4318,7 +4343,7 @@ sub display_search_results ($request_ref) {
 
 	my $current_link = '';
 
-	foreach my $field (multi_param()) {
+	foreach my $field (list_all_request_params($request_ref)) {
 		if (
 			   ($field eq "page")
 			or ($field eq "fields")
@@ -4584,7 +4609,7 @@ sub add_params_to_query ($request_ref, $query_ref) {
 
 	my $and = $query_ref->{"\$and"};
 
-	foreach my $field (multi_param()) {
+	foreach my $field (list_all_request_params($request_ref)) {
 
 		$log->debug("add_params_to_query - field", {field => $field}) if $log->is_debug();
 
@@ -4616,7 +4641,7 @@ sub add_params_to_query ($request_ref, $query_ref) {
 			# xyz_tags=-c	products without the c tag
 			# xyz_tags=a,b,-c,-d
 
-			my $values = remove_tags_and_quote(decode utf8 => single_param($field));
+			my $values = remove_tags_and_quote(request_param($request_ref, $field));
 
 			$log->debug("add_params_to_query - tags param",
 				{field => $field, lc => $lc, tag_lc => $tag_lc, values => $values})
@@ -4748,7 +4773,7 @@ sub add_params_to_query ($request_ref, $query_ref) {
 			# We can have multiple conditions, separated with a comma
 			# e.g. sugars_100g=>10,<=20
 
-			my $conditions = single_param($field);
+			my $conditions = request_param($request_ref, $field);
 
 			$log->debug("add_params_to_query - nutrient conditions", {field => $field, conditions => $conditions})
 				if $log->is_debug();
@@ -4766,7 +4791,7 @@ sub add_params_to_query ($request_ref, $query_ref) {
 				}
 				else {
 					$operator = '=';
-					$value = single_param($field);
+					$value = request_param($request_ref, $field);
 				}
 
 				$log->debug("add_params_to_query - nutrient condition",
@@ -4796,7 +4821,7 @@ sub add_params_to_query ($request_ref, $query_ref) {
 		# Exact match on a specific field (e.g. "code")
 		elsif (defined $valid_params{$field}) {
 
-			my $values = remove_tags_and_quote(decode utf8 => single_param($field));
+			my $values = remove_tags_and_quote(request_param($request_ref, $field));
 
 			# Possible values:
 			# xyz=a
diff --git a/lib/ProductOpener/Users.pm b/lib/ProductOpener/Users.pm
index c2a7c52a66056..a4c646abb9ec4 100644
--- a/lib/ProductOpener/Users.pm
+++ b/lib/ProductOpener/Users.pm
@@ -1088,8 +1088,7 @@ sub init_user ($request_ref) {
 				$user_id = $user_ref->{'userid'};
 				$log->context->{user_id} = $user_id;
 
-				my $hash_is_correct
-					= check_password_hash(encode_utf8(decode utf8 => request_param($request_ref, 'password')),
+				my $hash_is_correct = check_password_hash(encode_utf8(request_param($request_ref, 'password')),
 					$user_ref->{'encrypted_password'});
 				# We don't have the right password
 				if (not $hash_is_correct) {
diff --git a/tests/integration/expected_test_results/facets/brand_-brand1.json b/tests/integration/expected_test_results/facets/brand_-brand1.json
index bd6716c5a7c6a..f2e3f301e2dbf 100644
--- a/tests/integration/expected_test_results/facets/brand_-brand1.json
+++ b/tests/integration/expected_test_results/facets/brand_-brand1.json
@@ -1,7 +1,7 @@
 {
-   "count" : 8,
+   "count" : 9,
    "page" : 1,
-   "page_count" : 8,
+   "page_count" : 9,
    "page_size" : 24,
    "products" : [
       {
@@ -19,6 +19,9 @@
       {
          "product_name" : "Carrots - No label - Belgium - brand2"
       },
+      {
+         "product_name" : "Chocolate - Organic, Café Label - Martinique"
+      },
       {
          "product_name" : "Chocolate - Organic, Fair trade - Martinique"
       },
diff --git a/tests/integration/expected_test_results/facets/brand_unknown.json b/tests/integration/expected_test_results/facets/brand_unknown.json
index 7c7ce41ca6924..146f17cc9d8b9 100644
--- a/tests/integration/expected_test_results/facets/brand_unknown.json
+++ b/tests/integration/expected_test_results/facets/brand_unknown.json
@@ -1,7 +1,7 @@
 {
-   "count" : 5,
+   "count" : 6,
    "page" : 1,
-   "page_count" : 5,
+   "page_count" : 6,
    "page_size" : 24,
    "products" : [
       {
@@ -13,6 +13,9 @@
       {
          "product_name" : "Apples - Organic, Fair trade - France"
       },
+      {
+         "product_name" : "Chocolate - Organic, Café Label - Martinique"
+      },
       {
          "product_name" : "Chocolate - Organic, Fair trade - Martinique"
       },
diff --git a/tests/integration/expected_test_results/facets/category_-apples.json b/tests/integration/expected_test_results/facets/category_-apples.json
index 3d1fc27a2fafb..607e9907150ea 100644
--- a/tests/integration/expected_test_results/facets/category_-apples.json
+++ b/tests/integration/expected_test_results/facets/category_-apples.json
@@ -1,7 +1,7 @@
 {
-   "count" : 10,
+   "count" : 11,
    "page" : 1,
-   "page_count" : 10,
+   "page_count" : 11,
    "page_size" : 24,
    "products" : [
       {
@@ -22,6 +22,9 @@
       {
          "product_name" : "Carrots - Organic - France - brand1, brand2"
       },
+      {
+         "product_name" : "Chocolate - Organic, Café Label - Martinique"
+      },
       {
          "product_name" : "Chocolate - Organic, Fair trade - Martinique"
       },
diff --git a/tests/integration/expected_test_results/facets/category_-apples_label_organic.json b/tests/integration/expected_test_results/facets/category_-apples_label_organic.json
index 3dcaa4d1b27a5..03df4c72bd40c 100644
--- a/tests/integration/expected_test_results/facets/category_-apples_label_organic.json
+++ b/tests/integration/expected_test_results/facets/category_-apples_label_organic.json
@@ -1,7 +1,7 @@
 {
-   "count" : 7,
+   "count" : 8,
    "page" : 1,
-   "page_count" : 7,
+   "page_count" : 8,
    "page_size" : 24,
    "products" : [
       {
@@ -16,6 +16,9 @@
       {
          "product_name" : "Carrots - Organic - France - brand1, brand2"
       },
+      {
+         "product_name" : "Chocolate - Organic, Café Label - Martinique"
+      },
       {
          "product_name" : "Chocolate - Organic, Fair trade - Martinique"
       },
diff --git a/tests/integration/expected_test_results/facets/contributor-alice.json b/tests/integration/expected_test_results/facets/contributor-alice.json
index 5550899dc9fed..7093f96d13846 100644
--- a/tests/integration/expected_test_results/facets/contributor-alice.json
+++ b/tests/integration/expected_test_results/facets/contributor-alice.json
@@ -1,7 +1,7 @@
 {
-   "count" : 12,
+   "count" : 13,
    "page" : 1,
-   "page_count" : 12,
+   "page_count" : 13,
    "page_size" : 24,
    "products" : [
       {
@@ -31,6 +31,9 @@
       {
          "product_name" : "Carrots - Organic - France - brand1, brand2"
       },
+      {
+         "product_name" : "Chocolate - Organic, Café Label - Martinique"
+      },
       {
          "product_name" : "Chocolate - Organic, Fair trade - Martinique"
       },
diff --git a/tests/integration/expected_test_results/facets/de-accented-cafe-label.json b/tests/integration/expected_test_results/facets/de-accented-cafe-label.json
new file mode 100644
index 0000000000000..0804ea9932752
--- /dev/null
+++ b/tests/integration/expected_test_results/facets/de-accented-cafe-label.json
@@ -0,0 +1,17 @@
+{
+   "count" : 1,
+   "page" : 1,
+   "page_count" : 1,
+   "page_size" : 24,
+   "products" : [
+      {
+         "labels_tags" : [
+            "en:fair-trade",
+            "en:organic",
+            "de:café-label"
+         ],
+         "product_name" : "Chocolate - Organic, Café Label - Martinique"
+      }
+   ],
+   "skip" : 0
+}
diff --git a/tests/integration/facets.t b/tests/integration/facets.t
index 350a4a6fae3e1..3ba7830478a10 100644
--- a/tests/integration/facets.t
+++ b/tests/integration/facets.t
@@ -162,6 +162,18 @@ my @products = (
 			origins => "en:martinique",
 		),
 	},
+	# German product with accents in labels
+	{
+		%{dclone(\%empty_product_form)},
+		(
+			code => '200000000013',
+			product_name => "Chocolate - Organic, Café Label - Martinique",
+			categories => "en:chocolate",
+			labels => "en:organic,en:fair-trade,Café Label",
+			lang => "de",
+			lc => "de",
+		),
+	},
 );
 
 foreach my $product_ref (@products) {
@@ -175,7 +187,7 @@ edit_product(
 	{
 		%{dclone(\%empty_product_form)},
 		(
-			code => '200000000013',
+			code => '200000000101',
 			product_name => "Yogurt - Organic, Fair trade - Martinique",
 			categories => "en:yogurt",
 			labels => "en:organic,en:fair-trade",
@@ -310,6 +322,15 @@ my $tests_ref = [
 		expected_status_code => 200,
 		sort_products_by => 'product_name',
 	},
+	# accented facet value in German
+	{
+		test_case => 'de-accented-cafe-label',
+		method => 'GET',
+		subdomain => 'world-de',
+		path => '/label/café-label.json?fields=product_name,labels_tags',
+		expected_status_code => 200,
+		sort_products_by => 'product_name',
+	},
 ];
 
 # note: we need to execute the tests with bob, because we need authentication
diff --git a/tests/unit/display.t b/tests/unit/display.t
index 27dae373add04..613dbd081b6d7 100644
--- a/tests/unit/display.t
+++ b/tests/unit/display.t
@@ -199,4 +199,8 @@ display_tag($facets_ref);
 is($facets_ref->{'current_link'}, '/category/breads/data-quality');
 is($facets_ref->{'redirect'}, '/category/breads/data-quality');
 
+$request_ref->{body_json}{labels_tags} = 'en:organic';
+is(request_param($request_ref, 'unexisting_field'), undef);
+is(request_param($request_ref, 'labels_tags'), 'en:organic') or diag explain request_param($request_ref, 'labels_tags');
+
 done_testing();