How does PageSourceSearch know what pdfreaderpro.com is built with?

From the site's own source code. The crawler stores the exact bytes of its pages and first-party scripts; the libraries are recognised by fingerprinting that code against known releases, the identifiers are read out of the tag snippets, and the third-party hosts are the script, iframe and stylesheet sources in the HTML and the absolute URLs inside the scripts. Nothing is inferred from headers or guessed.

How far back does the history of pdfreaderpro.com go?

To the first crawl the timeline lists. Every crawl records what the site looked like; when a file's content changes, its earlier version stays viewable because the stored chunks are never deleted, only mapped. A crawl that finds a file unchanged adds no copy.

Can I see an older version of a script from pdfreaderpro.com?

Yes. In the stored files list, every date under a file opens the version that was live at that crawl, with the same viewer as the current one. The raw bytes can be downloaded from there.

Which other websites use the same tracking IDs as pdfreaderpro.com?

Each identifier links to its reverse lookup, the list of every site in the index whose source carries the same id: the sites one analytics property or tag manager container is shared across.

Site profile

pdfreaderpro.com

Built with gtm, gather-vue 8.20.3, @n8n/chat 1.39.2, @dearhive/dearflip-jquery-flipbook 1.7.3, facebook-sdk, element-plus 2.14.6, cloudflare-insights, @epigraph/configurator 2.7.0, @yes-chef/yes-chef-sliders 2.0.13, @epigraph/solutions 1.17.0, @vitest/utils 5.0.2, @bikematrix/web-components 1.3.23 and more. 5 pages and 146 stored files, last crawled 2026-10-02.

rank 400,143 30 libraries 4 identifiers 47 third-party hosts 1 crawl open the site

Technologies and libraries

Recognised by fingerprinting the stored files and bundles against known releases; a version is the release the bytes match.

Library	Version	Seen
gtm		2026-10-02
gather-vue	8.20.3	2026-10-02
@n8n/chat	1.39.2	2026-10-02
@dearhive/dearflip-jquery-flipbook	1.7.3	2026-10-02
facebook-sdk		2026-10-02
element-plus	2.14.6	2026-10-02
cloudflare-insights		2026-10-02
@epigraph/configurator	2.7.0	2026-10-02
@yes-chef/yes-chef-sliders	2.0.13	2026-10-02
@epigraph/solutions	1.17.0	2026-10-02
@vitest/utils	5.0.2	2026-10-02
@bikematrix/web-components	1.3.23	2026-10-02
@coveo/headless	3.57.0	2026-10-02
node-ray	3.0.0	2026-10-02
ngx-extended-pdf-viewer	30.0.1	2026-10-02
@cloudflare/realtimekit	2.0.2	2026-10-02
@etchteam/recycling-locator	1.78.1	2026-10-02
@myparcel-dev/delivery-options	7.5.3	2026-10-02
dealposbooks	6.29.4	2026-10-02
@cd2/fileboy-browser	0.15.4	2026-10-02
@pydantic/ai-chat-ui	2.3.0	2026-10-02
amis	6.13.0	2026-10-02
ramp-pcar	4.22.1	2026-10-02
@flowbase-co/boosters-tooltip	1.1.2	2026-09-24
pdf-parse	2.4.5	2026-09-24
@chatvolt/embeds	4.3.16	2026-09-24
@alfatech/livechat	2026.9.0-9.2	2026-09-24
@feedmepos/mf-menu	0.32.80-alpha.2	2026-09-24
twikoo	2.0.9	2026-09-24
pdfjs-viewer-element	4.1.0	2026-09-24

Tracking, tag and verification IDs

Public identifiers read out of the source. Each links to every other site in the index that carries the same one.

What	Value	Found in
Bing site verification (Microsoft)	A4EDAFB1E423DBFACF6D606F3DDDF038	view source
Facebook app id (Meta)	589202108156982	view source
Google site verification (Google)	jMy6Vki5PID6C8zUf4y3LdFIrLk9gVOHcuXS_4veLd4	view source
Google Tag Manager container (Google)	GTM-5DJF9KX	view source

Third-party hosts

Hosts outside pdfreaderpro.com that its pages load scripts, frames or stylesheets from, and that its own scripts name in absolute URLs (connect). Each links to every site loading from the same host.

Host	Loaded as	Found in
accounts.google.com	script connect	view source
adminconsole.lynxpdf.com	connect	view source
appleid.apple.com	connect	view source
appleid.cdn-apple.com	script connect	view source
apps.apple.com	connect	view source
beian.mps.gov.cn	connect	view source
cdn-apac.onetrust.com	script connect	view source
cdn.paddle.com	connect	view source
clarity.microsoft.com	connect	view source
cloud.google.com	connect	view source
connect.facebook.net	connect	view source
download.lynxpdf.com	connect	view source
element-plus.org	connect	view source
fonts.googleapis.com	stylesheet connect	view source
fonts.gstatic.com	connect	view source
github.com	connect	view source
login.microsoftonline.com	connect	view source
marketingplatform.google.com	connect	view source
pay.weixin.qq.com	connect	view source
pdfreaderpro.oss-cn-shanghai.aliyuncs.com	connect	view source
play.google.com	connect	view source
schema.org	connect	view source
static.cloudflareinsights.com	script	view source
support.apple.com	connect	view source
support.google.com	connect	view source
twitter.com	connect	view source
ui.awin.com	connect	view source
vuejs.org	connect	view source
web.lynxpdf.com	connect	view source
www.alipay.com	connect	view source
www.capterra.com	connect	view source
www.dottedsign.com	connect	view source
www.facebook.com	connect	view source
www.g2.com	connect	view source
www.getapp.com	connect	view source
www.googletagmanager.com	iframe connect	view source
www.linkedin.com	connect	view source
www.lynxpdf.com	connect	view source
www.microsoft.com	connect	view source
www.paddle.com	connect	view source
www.paypal.com	connect	view source
www.paypalobjects.com	connect	view source
www.softwareadvice.com	connect	view source
www.trustpilot.com	connect	view source
www.w3.org	connect	view source
www.youtube.com	connect	view source
www.zoho.com	connect	view source

Stored pages and scripts

The newest stored version of each file, newest first@if (p.FilesTruncated) { (the 500 newest of 146) }. Versions are the crawls at which the file was new or its content changed; each opens the file as it was then, rebuilt from the same stored chunks.

File	Kind	Size	Collected	Versions
https://connect.facebook.net/en_US/sdk.js	js library	not fetched	2026-10-02	current
https://static.cloudflareinsights.com/beacon.min…85bb4c19e7a9bdbcba1788362987495	js library	not fetched	2026-10-02	current
https://www.pdfreaderpro.com/pdf.worker.min.js	js	755.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BYZtoXCX.js	js	15.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/R0RipWGJ.js	js	16.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DXxWWwTr.js	js	17.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/YF8FNGcJ.js	js	12.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BAVxGG_v.js	js	307.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CeVzlWfP.js	js	10.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CwDkxh5n.js	js	13.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Kih2Ui8d.js	js	2.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C__Fjvmf.js	js	6.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/GmCAUinN.js	js	28.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Cn21HNY4.js	js	47 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/4XgHwSsQ.js	js	2.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BPVBlH0q.js	js	3.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CgOS1Gs3.js	js	23.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DwZLmid5.js	js	14.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CvyBNu9n.js	js	9.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DCcke8te.js	js	224.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Cs047424.js	js	18.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CZgoLugW.js	js	2.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BECrQOXZ.js	js	2.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C5w-6uKv.js	js	1.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/D57Vwbg4.js	js	44 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BDK-lP-M.js	js	25 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DVyRyAhc.js	js	24 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/w100707G.js	js	8.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/aR9q4klS.js	js	3.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CBf-E6Tw.js	js	3.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C5Yli1IF.js	js	22.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/gCHyY4Ht.js	js	4.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BVzw-ApU.js	js	9.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BMMQbgc4.js	js	5.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C0HBtBsO.js	js	8.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CmxMWWSs.js	js	2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DARGR773.js	js	12.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C0wmQW2T.js	js	6.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Br1ug4g6.js	js	24.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Cmw9zhoj.js	js	3.3 KB	2026-10-02	current
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https://www.pdfreaderpro.com/_nuxt/DcE7xICb.js	js	88.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BnLJ7zIo.js	js	13.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/4-sm7aZr.js	js	1.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/B7yXySZY.js	js	43.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/B2Ih7bQj.js	js	3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BizSS8vR.js	js	62.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Wt8MfvKi.js	js	2.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CTaIc5TD.js	js	16.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DZpEAIRe.js	js	29 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BGvM018j.js	js	36.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/5_k6cOQr.js	js	103.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/B1KdtllG.js	js	112.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Dp1xDQpq.js	js	2.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BgSXF_Rl.js	js	5.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DfB4n8PE.js	js	6.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/bg1v5S5i.js	js	27.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CvHKxJjn.js	js	11.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BTDvOnua.js	js	4.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/D5-taaY4.js	js	1.8 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Bup3iguM.js	js	27.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DVCs5JRk.js	js	9.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DrUSwjrE.js	js	1.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DmgHOvIu.js	js	10.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DQh4M1M-.js	js	8.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/y5Hk6Zif.js	js	127.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Cfrm0wBr.js	js	50 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/es3yNyqv.js	js	1.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BQkPIJ5h.js	js	3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BqL8wRmk.js	js	12.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DYgmGQf3.js	js	18.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/avT1WXet.js	js	21.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DMj4afVg.js	js	7.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BZEwjODR.js	js	19.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BP5oF7IP.js	js	2.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/l1ZrqLoI.js	js	2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/K_0__D7g.js	js	5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DayDMUAO.js	js	2.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Bkq3uLY8.js	js	18.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/4BoxKGD8.js	js	4.8 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DHCT-o-6.js	js	6.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CNPlMj9Y.js	js	23.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BfFMyYIn.js	js	53 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/aa06fSit.js	js	24.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BUInTPoW.js	js	21.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CyZyLadw.js	js	8.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/B5w9eTZz.js	js	1.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/D50EdVBl.js	js	13.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/UkhPd6E3.js	js	52 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CeIoOEbm.js	js	1.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/D3m1N1TV.js	js	53.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/sBNeS3pA.js	js	16.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/80-k24YT.js	js	7.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/p_V32EPO.js	js	4.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/cQMtZDWn.js	js	19.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/x4u0dHts.js	js	4.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CzFhXJZy.js	js	19.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/fV9iOLlg.js	js	6.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CyCwgn_l.js	js	7.8 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/d5NReE8u.js	js	52.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BTSZERYc.js	js	14.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DOjLdrb2.js	js	7.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/B9m_uWS6.js	js	6.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/AdYRW7-3.js	js	1.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BrYci_qR.js	js	9.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DPxsBenP.js	js	15.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/-mcNKYNU.js	js	3.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DceuM173.js	js	10.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BIsFm92k.js	js	17.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DHAtZela.js	js	724.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C3d3wqKz.js	js	4.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/D0Mfntrb.js	js	12.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CZwx1fTC.js	js	116.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/zzhgAwNV.js	js	6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CqC9KMqz.js	js	23.8 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DBqy54vn.js	js	30.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/ldE696OT.js	js	14.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DYkyfGp9.js	js	3.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/fSmVze03.js	js	1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DgSlKTLy.js	js	831 B	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/pLC0Na5t.js	js	971 B	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/6-J_clRH.js	js	30.7 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/ssT_21Og.js	js	1.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DNPEUenV.js	js	6.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/He1IkSir.js	js	102.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/JoMaC6ow.js	js	16.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/ChlPzZ6q.js	js	7.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C0CWAX6t.js	js	14.9 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/ChZYinXk.js	js	11.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CSXJbCrM.js	js	123.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DbEr8jmM.js	js	13.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C9Swyusq.js	js	20.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BEjybVXf.js	js	22.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/DaOXO3fs.js	js	14.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BjtrLWYA.js	js	18.1 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/zMKGUNPQ.js	js	28.2 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/9uCD4E8k.js	js	17.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/CPAyv84L.js	js	421.3 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/Dbkedzg2.js	js	29.8 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/C9Y_uNxu.js	js	132.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/_nuxt/BYPpdZKF.js	js	1013.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/blog/ilovepdf	html	413.8 KB	2026-10-02	2026-10-02
https://www.pdfreaderpro.com/store	html	296.6 KB	2026-10-02	current
https://www.pdfreaderpro.com/product	html	252.5 KB	2026-10-02	current
https://www.pdfreaderpro.com/login?redirect=/	html	180.4 KB	2026-10-02	current
https://www.pdfreaderpro.com/	html	372.3 KB	2026-10-02	current

Timeline

One entry per crawl, newest first, with what changed since the crawl before: libraries, identifiers, third-party hosts and files. Historical versions stay viewable because the stored chunks are shared between versions, never copied.

2026-10-02 first crawl

5 pages, 146 files, 7.5 MB; 23 libraries, 4 identifiers, 47 third-party hosts
23 libraries added
- gtm
- @vitest/utils 5.0.2
- gather-vue 8.20.3
- @etchteam/recycling-locator 1.78.1
- node-ray 3.0.0
- @myparcel-dev/delivery-options 7.5.3
- @pydantic/ai-chat-ui 2.3.0
- @cloudflare/realtimekit 2.0.2
- element-plus 2.14.6
- ramp-pcar 4.22.1
- @cd2/fileboy-browser 0.15.4
- dealposbooks 6.29.4
- and 11 more
4 identifiers added
- GTM-5DJF9KX Google Tag Manager container
- jMy6Vki5PID6C8zUf4y3LdFIrLk9gVOHcuXS_4veLd4 Google site verification
- A4EDAFB1E423DBFACF6D606F3DDDF038 Bing site verification
- 589202108156982 Facebook app id
52 third-party hosts added
146 files added

Questions about pdfreaderpro.com

How does PageSourceSearch know what pdfreaderpro.com is built with?: From the site's own source code. The crawler stores the exact bytes of its pages and first-party scripts; the libraries are recognised by fingerprinting that code against known releases, the identifiers are read out of the tag snippets, and the third-party hosts are the script, iframe and stylesheet sources in the HTML and the absolute URLs inside the scripts. Nothing is inferred from headers or guessed.
How far back does the history of pdfreaderpro.com go?: To the first crawl the timeline lists. Every crawl records what the site looked like; when a file's content changes, its earlier version stays viewable because the stored chunks are never deleted, only mapped. A crawl that finds a file unchanged adds no copy.
Can I see an older version of a script from pdfreaderpro.com?: Yes. In the stored files list, every date under a file opens the version that was live at that crawl, with the same viewer as the current one. The raw bytes can be downloaded from there.
Which other websites use the same tracking IDs as pdfreaderpro.com?: Each identifier links to its reverse lookup, the list of every site in the index whose source carries the same id: the sites one analytics property or tag manager container is shared across.

Look up another site, browse sites by tracking ID, third-party host or technology. Site owners: see the crawler page for how stored pages are removed.