Safe Pdf Reader?

I was trying to crop a scanned page when the whole window started strobing.

I had used Preview. If I slipped while scrolling, it would reformat the pdf and would sometimes remove the text layer. I have coordination issues and use a special mouse, keymapping, and Scroll+. Preview often takes attempts to scroll as attempts to select part of the page and do *something*.

I can't download Adobe reader. I am photosensitive. Adobe's site sometimes strobes.

I often need to repair pdf files to make them compatible with Skim, Preview, and my old Kindle, and to compress them, but I don't want to add to them. Most "pdf editing" tools seem to be aimed at adding to them. I would like to convert most to epub and mobi, but haven't found adequate tools.

For the moment, I've switched back to Preview.

Are there any apps, besides the pdf readers themselves, that can link to a specific page of a pdf? If so, I could use these to create bookmark lists for different projects.

I don't think I can access the new-style Preview bookmarks from outside the file, so I can't use them to create bokmark lists for each project, and I know I can't access the new-style Preview Bookmarks on the Kindle, so I can't use them to work around the very limited Kindle pdf handling.

I've also had occasional screen flashing in other applications, so I doubt it's a Skim or PdfKit issue. Maybe something with the displays? I use an external monitor and I use a reduced resolution for larger text.

Got strobed again, this time while selecting the Etrecheck results.

EtreCheck version: 3.2.3 (363)

Report generated 2017-05-03 20:29:00

Download EtreCheck from https://etrecheck.com

Runtime: 2:13

Performance: Excellent

Click the [Lookup] links for more information from Apple Support Communities.

Click the [Details] links for more information about that line.

Problem: Other problem

Description:

GORRAM STROBING

Hardware Information: ⓘ

MacBook Air

[Technical Specifications] - [User Guide] - [Warranty & Service]

MacBook Air - model: MacBookAir6,1

1 1.3 GHz Intel Core i5 (i5-4250U) CPU: 2-core

8 GB RAM Not upgradeable

BANK 0/DIMM0

4 GB DDR3 1600 MHz ok

BANK 1/DIMM0

4 GB DDR3 1600 MHz ok

Bluetooth: Good - Handoff/Airdrop2 supported

Wireless: en0: 802.11 a/b/g/n/ac

Battery: Health = Normal - Cycle count = 48

Video Information: ⓘ

Intel HD Graphics 5000

Color LCD 1920 x 1080

DELL E2414H 1920 x 1080 @ 60 Hz

System Software: ⓘ

macOS Sierra 10.12.4 (16E195) - Time since boot: about 8 hours

Disk Information: ⓘ

APPLE SSD SD0256F disk0 : (251 GB) (Solid State - TRIM: Yes)

[Show SMART report]

EFI (disk0s1) <not mounted> : 210 MB

Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB

Macintosh HD (disk1) / [Startup]: 249.79 GB (24.26 GB free)

Core Storage: disk0s2 250.14 GB Online

USB Information: ⓘ

TOSHIBA External USB 3.0

Apple Inc. BRCM20702 Hub

Apple Inc. Bluetooth USB Host Controller

Kingsis Peripherals Evoluent VerticalMouse 4

Thunderbolt Information: ⓘ

Apple Inc. thunderbolt_bus

Gatekeeper: ⓘ

Mac App Store and identified developers

Kernel Extensions: ⓘ

/Library/Extensions

[loaded] com.evoluent.driver.VerticalMouseDriver (1.2.0f1 - SDK 10.11 - 2017-05-03) [Lookup]

System Launch Agents: ⓘ

[not loaded] 7 Apple tasks

[loaded] 180 Apple tasks

[running] 95 Apple tasks

System Launch Daemons: ⓘ

[not loaded] 41 Apple tasks

[loaded] 175 Apple tasks

[running] 103 Apple tasks

Launch Agents: ⓘ

[running] com.evoluent.agent.plist (2016-12-30) [Lookup]

[running] com.uc.NotifiTest.plist (2015-11-04) [Lookup]

[running] com.uc.pentablet.plist (2015-11-04) [Lookup]

[loaded] org.gpgtools.Libmacgpg.xpc.plist ✔︎ (2016-06-28) [Lookup]

[loaded] org.gpgtools.gpgmail.enable-bundles.plist § (2015-09-21) [Lookup]

[loaded] org.gpgtools.gpgmail.patch-uuid-user.plist (2015-09-21) [Lookup]

[loaded] org.gpgtools.macgpg2.fix.plist § (2016-06-28) [Lookup]

[running] org.gpgtools.macgpg2.shutdown-gpg-agent.plist § (2016-06-28) [Lookup]

[loaded] org.gpgtools.updater.plist ✔︎ (2016-07-05) [Lookup]

[loaded] org.macosforge.xquartz.startx.plist ✔︎ (2016-05-05) [Lookup]

Launch Daemons: ⓘ

[loaded] com.malwarebytes.HelperTool.plist ✔︎ (2017-03-07) [Lookup]

[loaded] com.zeroonetwenty.BlueHarvestHelper630.plist ✔︎ (2016-05-31) [Lookup]

[loaded] org.gpgtools.gpgmail.patch-uuid.plist (2015-09-21) [Lookup]

[loaded] org.macosforge.xquartz.privileged_startx.plist ✔︎ (2016-05-05) [Lookup]

User Launch Agents: ⓘ

[loaded] com.dropbox.DropboxMacUpdate.agent.plist ✔︎ (2017-05-02) [Lookup]

[loaded] com.valvesoftware.steamclean.plist (2017-05-03) [Lookup]

User Login Items: ⓘ

iTunesHelper Application (2017-03-23)

(/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)

CustomMenu Application

(/Applications/CustomMenu.app)

Scroll+ Application

(/Applications/Scroll+.app)

Dropbox Application

(/Applications/Dropbox.app)

Internet Plug-ins: ⓘ

npDDRia: 0.0.14.5 - SDK 10.9 (2015-08-19) [Lookup]

QuickTime Plugin: 7.7.3 (2017-03-31)

Safari Extensions: ⓘ

Adguard AdBlocker - adguard - http://adguard.com (2017-02-23)

Hide Images - Giancarlo Erra - http://www.hideimages.net (2016-01-22)

Open-Dyslexic - Abelardo Gonzalez - http://dyslexicfonts.com (2013-08-05)

AnySearch - Matt Swain - http://matt-swain.com/extensions (2016-05-11)

DuckDuckGo - DuckDuckGo - http://duckduckgo.com (2017-03-27)

Deanimator - Mat Sadler - http://github.com/matsadler/deanimator (2016-12-27)

Translate - SideTree.com - Apps for Mac and Web - http://SideTree.com/extensions.html#Translate (2016-01-30)

Stylish - Vladimir Sobolev - http://sobolev.us/stylish (2017-03-27)

3rd Party Preference Panes: ⓘ

Evoluent (2016-12-02) [Lookup]

GPGPreferences (2016-07-05) [Lookup]

Time Machine: ⓘ

Skip System Files: NO

Mobile backups: ON

Auto backup: YES

Volumes being backed up:

Macintosh HD: Disk size: 249.79 GB Disk used: 225.53 GB

Destinations:

Time Machine 2015 [Local]

Total size: 999.86 GB

Total number of backups: 111

Oldest backup: 10/27/15, 9:17 PM

Last backup: 5/3/17, 7:33 PM

Size of backup disk: Excellent

Backup size 999.86 GB > (Disk size 249.79 GB X 3)

Top Processes by CPU: ⓘ

37% firefox

11% WindowServer

4% kernel_task

3% hidd

2% Scroll+

Top Processes by Memory: ⓘ

983 MB firefox

788 MB kernel_task

573 MB Scroll+

254 MB mdworker(7)

213 MB Dropbox

Virtual Memory Information: ⓘ

3.29 GB Available RAM

207 MB Free RAM

4.71 GB Used RAM

3.08 GB Cached files

0 B Swap Used

Diagnostics Information: ⓘ

2017-05-03 16:19:36 /Library/Logs/DiagnosticReports/firefox_2017-05-03-161936_[redacted].cpu_resour ce.diag [Details]

/Applications/Firefox.app/Contents/MacOS/firefox

2017-05-03 12:22:32 Self test - passed

2017-05-02 17:48:23 /Library/Logs/DiagnosticReports/Elucidate_2017-05-02-174823_[redacted].cpu_reso urce.diag [Details]

/Applications/Elucidate.app/Contents/MacOS/Elucidate

2017-05-02 17:08:16 /Library/Logs/DiagnosticReports/firefox_2017-05-02-170816_[redacted].cpu_resour ce.diag [Details]

2017-05-02 16:24:16 /Library/Logs/DiagnosticReports/DjVu Reader FS_2017-05-02-162416_[redacted].cpu_resource.diag [Details]

/Applications/DjVu Reader FS.app/Contents/MacOS/DjVu Reader FS

2017-05-02 11:01:58 /Library/Logs/DiagnosticReports/firefox_2017-05-02-110158_[redacted].cpu_resour ce.diag [Details]

2017-05-01 23:37:17 /Library/Logs/DiagnosticReports/PDFGenius_2017-05-01-233717_[redacted].cpu_reso urce.diag [Details]

/Applications/PDFGenius.app/Contents/MacOS/PDFGenius