Finally the Blogger Thumbnail Can Support WEBP - This is the
result of my imprisonment that I have done for almost 4 weeks, hahaha ... (just
kidding, so don't think so ...). An inspiration finally stopped in my head for
Blogger thumbnail solutions to support WEBP.
The problem of presenting images in the next-gen format that
came from Blogger thumbnails when tested using Pagespeed Insights and
Lighthouse is still an unsolved case because Blogger does not yet support the
WEBP image format for thumbnails.
As for the picture posting, it can already be good for AMP
and for NON AMP. You can refer to the post about how to convert Blogger images
into WebP for amp-img and WebP images on Non-AMP Blogger posts .
But finally I got a solution for Blogger thumbnails to
support WEBP with the help of Statically Imgpx and Lazysizes.js . But this is
still only for Non AMP, for AMP I have not got the solution.
I made use of the Statically Imgpx feature to change Blogger
images to support WEBP by using Lazysizes.js to change the URL of the image as
well as to lazyload the image.
So with this, 2 problems in Pagespeed Insights and
Lighthouse can be resolved, namely Serve images in next-gen formats and Defer
offscreen images .
With Lazysizes.js, I changed the Blogger image URL to the
following by slightly modifying the script.
Original URL:
https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhHsEsekLgUqo8CoBKjSNqHYe5_HhhIxugsrQw4xoyg7YhZWGAPBatbdgiNybp7-OK_XzifiNyq2pKv36nwrhLM5OhbXABVZ_xV8MwO8Nc0rSsH4nIGggB-c-xm1W9FKehPG6uWU1qqARM/w600-h337-p-k-no-nu/Km6K4E05HjM.jpg
Modified Lazysizes URL and blogger thumbnail code:
https://cdn.statically.io/img/3.bp.blogspot.com/-WvjDGI4wI1Q/XSmKyEfpsuI/AAAAAAAADqc/GGdZ0RndJGc8xBTn3myp0THfQltQKK2vQCLcBGAs/w600-h337-p-k-no-nu/Km6K4E05HjM.jpg?format=webp
Modified Lazysizes URL and blogger thumbnail code:
/*! lazysizes - v5.1.0 */
!function(a,b){var c=b(a,a.document);a.lazySizes=c,"object"==typeof module&&module.exports&&(module.exports=c)}("undefined"!=typeof window?window:{},function(a,b){"use strict";var c,d;if(function(){var b,c={lazyClass:"lazyload",loadedClass:"lazyloaded",loadingClass:"lazyloading",preloadClass:"lazypreload",errorClass:"lazyerror",autosizesClass:"lazyautosizes",srcAttr:"data-src",srcsetAttr:"data-srcset",sizesAttr:"data-sizes",minSize:40,customMedia:{},init:!0,expFactor:1.5,hFac:.8,loadMode:2,loadHidden:!0,ricTimeout:0,throttleDelay:125};d=a.lazySizesConfig||a.lazysizesConfig||{};for(b in c)b in d||(d[b]=c[b])}(),!b||!b.getElementsByClassName)return{init:function(){},cfg:d,noSupport:!0};var e=b.documentElement,f=a.Date,g=a.HTMLPictureElement,h="addEventListener",i="getAttribute",j=a[h],k=a.setTimeout,l=a.requestAnimationFrame||k,m=a.requestIdleCallback,n=/^picture$/i,o=["load","error","lazyincluded","_lazyloaded"],p={},q=Array.prototype.forEach,r=function(a,b){return p[b]||(p[b]=new RegExp("(\\s|^)"+b+"(\\s|$)")),p[b].test(a[i]("class")||"")&&p[b]},s=function(a,b){r(a,b)||a.setAttribute("class",(a[i]("class")||"").trim()+" "+b)},t=function(a,b){var c;(c=r(a,b))&&a.setAttribute("class",(a[i]("class")||"").replace(c," "))},u=function(a,b,c){var d=c?h:"removeEventListener";c&&u(a,b),o.forEach(function(c){a[d](c,b)})},v=function(a,d,e,f,g){var h=b.createEvent("Event");return e||(e={}),e.instance=c,h.initEvent(d,!f,!g),h.detail=e,a.dispatchEvent(h),h},w=function(b,c){var e;!g&&(e=a.picturefill||d.pf)?(c&&c.src&&!b[i]("srcset")&&b.setAttribute("srcset",c.src),e({reevaluate:!0,elements:[b]})):c&&c.src&&(b.src=c.src)},x=function(a,b){return(getComputedStyle(a,null)||{})[b]},y=function(a,b,c){for(c=c||a.offsetWidth;c<d.minSize&&b&&!a._lazysizesWidth;)c=b.offsetWidth,b=b.parentNode;return c},z=function(){var a,c,d=[],e=[],f=d,g=function(){var b=f;for(f=d.length?e:d,a=!0,c=!1;b.length;)b.shift()();a=!1},h=function(d,e){a&&!e?d.apply(this,arguments):(f.push(d),c||(c=!0,(b.hidden?k:l)(g)))};return h._lsFlush=g,h}(),A=function(a,b){return b?function(){z(a)}:function(){var b=this,c=arguments;z(function(){a.apply(b,c)})}},B=function(a){var b,c=0,e=d.throttleDelay,g=d.ricTimeout,h=function(){b=!1,c=f.now(),a()},i=m&&g>49?function(){m(h,{timeout:g}),g!==d.ricTimeout&&(g=d.ricTimeout)}:A(function(){k(h)},!0);return function(a){var d;(a=!0===a)&&(g=33),b||(b=!0,d=e-(f.now()-c),d<0&&(d=0),a||d<9?i():k(i,d))}},C=function(a){var b,c,d=99,e=function(){b=null,a()},g=function(){var a=f.now()-c;a<d?k(g,d-a):(m||e)(e)};return function(){c=f.now(),b||(b=k(g,d))}},D=function(){var g,l,m,o,p,y,D,F,G,H,I,J,K=/^img$/i,L=/^iframe$/i,M="onscroll"in a&&!/(gle|ing)bot/.test(navigator.userAgent),N=0,O=0,P=0,Q=-1,R=function(a){P--,(!a||P<0||!a.target)&&(P=0)},S=function(a){return null==J&&(J="hidden"==x(b.body,"visibility")),J||"hidden"!=x(a.parentNode,"visibility")&&"hidden"!=x(a,"visibility")},T=function(a,c){var d,f=a,g=S(a);for(F-=c,I+=c,G-=c,H+=c;g&&(f=f.offsetParent)&&f!=b.body&&f!=e;)(g=(x(f,"opacity")||1)>0)&&"visible"!=x(f,"overflow")&&(d=f.getBoundingClientRect(),g=H>d.left&&G<d.right&&I>d.top-1&&F<d.bottom+1);return g},U=function(){var a,f,h,j,k,m,n,p,q,r,s,t,u=c.elements;if((o=d.loadMode)&&P<8&&(a=u.length)){for(f=0,Q++;f<a;f++)if(u[f]&&!u[f]._lazyRace)if(!M||c.prematureUnveil&&c.prematureUnveil(u[f]))aa(u[f]);else if((p=u[f][i]("data-expand"))&&(m=1*p)||(m=O),r||(r=!d.expand||d.expand<1?e.clientHeight>500&&e.clientWidth>500?500:370:d.expand,c._defEx=r,s=r*d.expFactor,t=d.hFac,J=null,O<s&&P<1&&Q>2&&o>2&&!b.hidden?(O=s,Q=0):O=o>1&&Q>1&&P<6?r:N),q!==m&&(y=innerWidth+m*t,D=innerHeight+m,n=-1*m,q=m),h=u[f].getBoundingClientRect(),(I=h.bottom)>=n&&(F=h.top)<=D&&(H=h.right)>=n*t&&(G=h.left)<=y&&(I||H||G||F)&&(d.loadHidden||S(u[f]))&&(l&&P<3&&!p&&(o<3||Q<4)||T(u[f],m))){if(aa(u[f]),k=!0,P>9)break}else!k&&l&&!j&&P<4&&Q<4&&o>2&&(g[0]||d.preloadAfterLoad)&&(g[0]||!p&&(I||H||G||F||"auto"!=u[f][i](d.sizesAttr)))&&(j=g[0]||u[f]);j&&!k&&aa(j)}},V=B(U),W=function(a){var b=a.target;if(b._lazyCache)return void delete b._lazyCache;R(a),s(b,d.loadedClass),t(b,d.loadingClass),u(b,Y),v(b,"lazyloaded")},X=A(W),Y=function(a){X({target:a.target})},Z=function(a,b){try{a.contentWindow.location.replace(b)}catch(c){a.src=b}},$=function(a){var b,c=a[i](d.srcsetAttr).replace(/.*?:\/\//g,"https://cdn.statically.io/img/");(b=d.customMedia[a[i]("data-media")||a[i]("media")])&&a.setAttribute("media",b),c&&a.setAttribute("srcset",c)},_=A(function(a,b,c,e,f){var g,h,j,l,o,p;(o=v(a,"lazybeforeunveil",b)).defaultPrevented||(e&&(c?s(a,d.autosizesClass):a.setAttribute("sizes",e)),h=a[i](d.srcsetAttr),g=a[i](d.srcAttr).replace(/.*?:\/\//g,"//"),f&&(j=a.parentNode,l=j&&n.test(j.nodeName||"")),p=b.firesLoad||"src"in a&&(h||g||l),o={target:a},s(a,d.loadingClass),p&&(clearTimeout(m),m=k(R,2500),u(a,Y,!0)),l&&q.call(j.getElementsByTagName("source"),$),h?a.setAttribute("srcset",h):g&&!l&&(L.test(a.nodeName)?Z(a,g):a.src=g),f&&(h||l)&&w(a,{src:g})),a._lazyRace&&delete a._lazyRace,t(a,d.lazyClass),z(function(){var b=a.complete&&a.naturalWidth>1;p&&!b||(b&&s(a,"ls-is-cached"),W(o),a._lazyCache=!0,k(function(){"_lazyCache"in a&&delete a._lazyCache},9)),"lazy"==a.loading&&P--},!0)}),aa=function(a){if(!a._lazyRace){var b,c=K.test(a.nodeName),e=c&&(a[i](d.sizesAttr)||a[i]("sizes")),f="auto"==e;(!f&&l||!c||!a[i]("src")&&!a.srcset||a.complete||r(a,d.errorClass)||!r(a,d.lazyClass))&&(b=v(a,"lazyunveilread").detail,f&&E.updateElem(a,!0,a.offsetWidth),a._lazyRace=!0,P++,_(a,b,f,e,c))}},ba=C(function(){d.loadMode=3,V()}),ca=function(){3==d.loadMode&&(d.loadMode=2),ba()},da=function(){if(!l){if(f.now()-p<999)return void k(da,999);l=!0,d.loadMode=3,V(),j("scroll",ca,!0)}};return{_:function(){p=f.now(),c.elements=b.getElementsByClassName(d.lazyClass),g=b.getElementsByClassName(d.lazyClass+" "+d.preloadClass),j("scroll",V,!0),j("resize",V,!0),a.MutationObserver?new MutationObserver(V).observe(e,{childList:!0,subtree:!0,attributes:!0}):(e[h]("DOMNodeInserted",V,!0),e[h]("DOMAttrModified",V,!0),setInterval(V,999)),j("hashchange",V,!0),["focus","mouseover","click","load","transitionend","animationend"].forEach(function(a){b[h](a,V,!0)}),/d$|^c/.test(b.readyState)?da():(j("load",da),b[h]("DOMContentLoaded",V),k(da,2e4)),c.elements.length?(U(),z._lsFlush()):V()},checkElems:V,unveil:aa,_aLSL:ca}}(),E=function(){var a,c=A(function(a,b,c,d){var e,f,g;if(a._lazysizesWidth=d,d+="px",a.setAttribute("sizes",d),n.test(b.nodeName||""))for(e=b.getElementsByTagName("source"),f=0,g=e.length;f<g;f++)e[f].setAttribute("sizes",d);c.detail.dataAttr||w(a,c.detail)}),e=function(a,b,d){var e,f=a.parentNode;f&&(d=y(a,f,d),e=v(a,"lazybeforesizes",{width:d,dataAttr:!!b}),e.defaultPrevented||(d=e.detail.width)&&d!==a._lazysizesWidth&&c(a,f,e,d))},f=function(){var b,c=a.length;if(c)for(b=0;b<c;b++)e(a[b])},g=C(f);return{_:function(){a=b.getElementsByClassName(d.autosizesClass),j("resize",g)},checkElems:g,updateElem:e}}(),F=function(){!F.i&&b.getElementsByClassName&&(F.i=!0,E._(),D._())};return k(function(){d.init&&F()}),c={cfg:d,autoSizer:E,loader:D,init:F,uP:w,aC:s,rC:t,hC:r,fire:v,gW:y,rAF:z}});
<b:if cond='data:post.thumbnailUrl'>
<picture>
<source expr:data-srcset='resizeImage(data:post.thumbnailUrl, 600, "16:9") + "?format=webp"' type='image/webp'/>
<source expr:data-srcset='resizeImage(data:post.thumbnailUrl, 600, "16:9")' type='image/jpg'/>
<img class='lazyload' expr:alt='data:post.title' expr:data-src='resizeImage(data:post.thumbnailUrl, 600, "16:9")' expr:title='data:post.title' height='9' src='data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAJAQMAAAAB5D5xAAAAA1BMVEUAAACnej3aAAAAAXRSTlMAQObYZgAAAApJREFUCNdjwA0AABsAAQrj5HwAAAAASUVORK5CYII=' width='16'/>
</picture>
</b:if><b:if cond='data:post.thumbnail'>
<div class='item-thumbnail'>
<picture>
<source expr:data-srcset='resizeImage(data:post.thumbnail, 138, "16:9") + "?format=webp"' type='image/webp'/>
<source expr:data-srcset='resizeImage(data:post.thumbnail, 138, "16:9")' type='image/jpg'/>
<img class='lazyload' expr:alt='data:post.title' expr:data-src='resizeImage(data:post.thumbnail, 138, "16:9")' expr:title='data:post.title' height='9' src='data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAJAQMAAAAB5D5xAAAAA1BMVEUAAACnej3aAAAAAXRSTlMAQObYZgAAAApJREFUCNdjwA0AABsAAQrj5HwAAAAASUVORK5CYII=' width='16'/>
</picture></div>
</b:if>For the size and dimensions of the image in the code above, please adjust to the needs of your blog.
Maybe someone asks, why use the <picture> tag? Because
until now not all browsers support WEBP image format. With the <picture>
tag, there we also provide a fallback image * .jpg for browsers that don't
support WEBP.
What I expect from Blogger, can modify blogger thumbnail
code like to resizeImage so that we can modify the url for blogger image
parameters.
May be useful.