diff --git a/packages/parse5/lib/common/foreign-content.ts b/packages/parse5/lib/common/foreign-content.ts
index 9981363e5..2b9ffadff 100644
--- a/packages/parse5/lib/common/foreign-content.ts
+++ b/packages/parse5/lib/common/foreign-content.ts
@@ -10,66 +10,68 @@ const MIME_TYPES = {
 //Attributes
 const DEFINITION_URL_ATTR = 'definitionurl';
 const ADJUSTED_DEFINITION_URL_ATTR = 'definitionURL';
-const SVG_ATTRS_ADJUSTMENT_MAP = new Map([
-    ['attributename', 'attributeName'],
-    ['attributetype', 'attributeType'],
-    ['basefrequency', 'baseFrequency'],
-    ['baseprofile', 'baseProfile'],
-    ['calcmode', 'calcMode'],
-    ['clippathunits', 'clipPathUnits'],
-    ['diffuseconstant', 'diffuseConstant'],
-    ['edgemode', 'edgeMode'],
-    ['filterunits', 'filterUnits'],
-    ['glyphref', 'glyphRef'],
-    ['gradienttransform', 'gradientTransform'],
-    ['gradientunits', 'gradientUnits'],
-    ['kernelmatrix', 'kernelMatrix'],
-    ['kernelunitlength', 'kernelUnitLength'],
-    ['keypoints', 'keyPoints'],
-    ['keysplines', 'keySplines'],
-    ['keytimes', 'keyTimes'],
-    ['lengthadjust', 'lengthAdjust'],
-    ['limitingconeangle', 'limitingConeAngle'],
-    ['markerheight', 'markerHeight'],
-    ['markerunits', 'markerUnits'],
-    ['markerwidth', 'markerWidth'],
-    ['maskcontentunits', 'maskContentUnits'],
-    ['maskunits', 'maskUnits'],
-    ['numoctaves', 'numOctaves'],
-    ['pathlength', 'pathLength'],
-    ['patterncontentunits', 'patternContentUnits'],
-    ['patterntransform', 'patternTransform'],
-    ['patternunits', 'patternUnits'],
-    ['pointsatx', 'pointsAtX'],
-    ['pointsaty', 'pointsAtY'],
-    ['pointsatz', 'pointsAtZ'],
-    ['preservealpha', 'preserveAlpha'],
-    ['preserveaspectratio', 'preserveAspectRatio'],
-    ['primitiveunits', 'primitiveUnits'],
-    ['refx', 'refX'],
-    ['refy', 'refY'],
-    ['repeatcount', 'repeatCount'],
-    ['repeatdur', 'repeatDur'],
-    ['requiredextensions', 'requiredExtensions'],
-    ['requiredfeatures', 'requiredFeatures'],
-    ['specularconstant', 'specularConstant'],
-    ['specularexponent', 'specularExponent'],
-    ['spreadmethod', 'spreadMethod'],
-    ['startoffset', 'startOffset'],
-    ['stddeviation', 'stdDeviation'],
-    ['stitchtiles', 'stitchTiles'],
-    ['surfacescale', 'surfaceScale'],
-    ['systemlanguage', 'systemLanguage'],
-    ['tablevalues', 'tableValues'],
-    ['targetx', 'targetX'],
-    ['targety', 'targetY'],
-    ['textlength', 'textLength'],
-    ['viewbox', 'viewBox'],
-    ['viewtarget', 'viewTarget'],
-    ['xchannelselector', 'xChannelSelector'],
-    ['ychannelselector', 'yChannelSelector'],
-    ['zoomandpan', 'zoomAndPan'],
-]);
+const SVG_ATTRS_ADJUSTMENT_MAP = new Map(
+    [
+        'attributeName',
+        'attributeType',
+        'baseFrequency',
+        'baseProfile',
+        'calcMode',
+        'clipPathUnits',
+        'diffuseConstant',
+        'edgeMode',
+        'filterUnits',
+        'glyphRef',
+        'gradientTransform',
+        'gradientUnits',
+        'kernelMatrix',
+        'kernelUnitLength',
+        'keyPoints',
+        'keySplines',
+        'keyTimes',
+        'lengthAdjust',
+        'limitingConeAngle',
+        'markerHeight',
+        'markerUnits',
+        'markerWidth',
+        'maskContentUnits',
+        'maskUnits',
+        'numOctaves',
+        'pathLength',
+        'patternContentUnits',
+        'patternTransform',
+        'patternUnits',
+        'pointsAtX',
+        'pointsAtY',
+        'pointsAtZ',
+        'preserveAlpha',
+        'preserveAspectRatio',
+        'primitiveUnits',
+        'refX',
+        'refY',
+        'repeatCount',
+        'repeatDur',
+        'requiredExtensions',
+        'requiredFeatures',
+        'specularConstant',
+        'specularExponent',
+        'spreadMethod',
+        'startOffset',
+        'stdDeviation',
+        'stitchTiles',
+        'surfaceScale',
+        'systemLanguage',
+        'tableValues',
+        'targetX',
+        'targetY',
+        'textLength',
+        'viewBox',
+        'viewTarget',
+        'xChannelSelector',
+        'yChannelSelector',
+        'zoomAndPan',
+    ].map((attr) => [attr.toLowerCase(), attr])
+);
 
 const XML_ATTRS_ADJUSTMENT_MAP = new Map([
     ['xlink:actuate', { prefix: 'xlink', name: 'actuate', namespace: NS.XLINK }],
@@ -87,44 +89,46 @@ const XML_ATTRS_ADJUSTMENT_MAP = new Map([
 ]);
 
 //SVG tag names adjustment map
-export const SVG_TAG_NAMES_ADJUSTMENT_MAP = new Map([
-    ['altglyph', 'altGlyph'],
-    ['altglyphdef', 'altGlyphDef'],
-    ['altglyphitem', 'altGlyphItem'],
-    ['animatecolor', 'animateColor'],
-    ['animatemotion', 'animateMotion'],
-    ['animatetransform', 'animateTransform'],
-    ['clippath', 'clipPath'],
-    ['feblend', 'feBlend'],
-    ['fecolormatrix', 'feColorMatrix'],
-    ['fecomponenttransfer', 'feComponentTransfer'],
-    ['fecomposite', 'feComposite'],
-    ['feconvolvematrix', 'feConvolveMatrix'],
-    ['fediffuselighting', 'feDiffuseLighting'],
-    ['fedisplacementmap', 'feDisplacementMap'],
-    ['fedistantlight', 'feDistantLight'],
-    ['feflood', 'feFlood'],
-    ['fefunca', 'feFuncA'],
-    ['fefuncb', 'feFuncB'],
-    ['fefuncg', 'feFuncG'],
-    ['fefuncr', 'feFuncR'],
-    ['fegaussianblur', 'feGaussianBlur'],
-    ['feimage', 'feImage'],
-    ['femerge', 'feMerge'],
-    ['femergenode', 'feMergeNode'],
-    ['femorphology', 'feMorphology'],
-    ['feoffset', 'feOffset'],
-    ['fepointlight', 'fePointLight'],
-    ['fespecularlighting', 'feSpecularLighting'],
-    ['fespotlight', 'feSpotLight'],
-    ['fetile', 'feTile'],
-    ['feturbulence', 'feTurbulence'],
-    ['foreignobject', 'foreignObject'],
-    ['glyphref', 'glyphRef'],
-    ['lineargradient', 'linearGradient'],
-    ['radialgradient', 'radialGradient'],
-    ['textpath', 'textPath'],
-]);
+export const SVG_TAG_NAMES_ADJUSTMENT_MAP = new Map(
+    [
+        'altGlyph',
+        'altGlyphDef',
+        'altGlyphItem',
+        'animateColor',
+        'animateMotion',
+        'animateTransform',
+        'clipPath',
+        'feBlend',
+        'feColorMatrix',
+        'feComponentTransfer',
+        'feComposite',
+        'feConvolveMatrix',
+        'feDiffuseLighting',
+        'feDisplacementMap',
+        'feDistantLight',
+        'feFlood',
+        'feFuncA',
+        'feFuncB',
+        'feFuncG',
+        'feFuncR',
+        'feGaussianBlur',
+        'feImage',
+        'feMerge',
+        'feMergeNode',
+        'feMorphology',
+        'feOffset',
+        'fePointLight',
+        'feSpecularLighting',
+        'feSpotLight',
+        'feTile',
+        'feTurbulence',
+        'foreignObject',
+        'glyphRef',
+        'linearGradient',
+        'radialGradient',
+        'textPath',
+    ].map((tn) => [tn.toLowerCase(), tn])
+);
 
 //Tags that causes exit from foreign content
 const EXITS_FOREIGN_CONTENT = new Set<string>([
@@ -198,7 +202,7 @@ export function adjustTokenSVGAttrs(token: TagToken) {
     for (let i = 0; i < token.attrs.length; i++) {
         const adjustedAttrName = SVG_ATTRS_ADJUSTMENT_MAP.get(token.attrs[i].name);
 
-        if (adjustedAttrName) {
+        if (adjustedAttrName != null) {
             token.attrs[i].name = adjustedAttrName;
         }
     }
@@ -219,7 +223,7 @@ export function adjustTokenXMLAttrs(token: TagToken) {
 export function adjustTokenSVGTagName(token: TagToken) {
     const adjustedTagName = SVG_TAG_NAMES_ADJUSTMENT_MAP.get(token.tagName);
 
-    if (adjustedTagName) {
+    if (adjustedTagName != null) {
         token.tagName = adjustedTagName;
     }
 }